Vishay Intertechnology (VSH) 10-Q 8 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	3 Months Ended
	Mar. 31, 2018	May 04, 2018	Jul. 01, 2017
Entity Information [Line Items]
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Entity Registrant Name	VISHAY INTERTECHNOLOGY INC
Entity Central Index Key	103,730
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 2,237,000,000
Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		132,117,715
Class B Convertible Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		12,097,427

Consolidated Condensed Balance

Consolidated Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 839,591	$ 748,032
Short-term investments	501,221	547,136
Accounts receivable, net	376,537	340,027
Inventories:
Finished goods	132,996	127,272
Work in process	184,613	170,319
Raw materials	143,039	132,068
Total inventories	460,648	429,659
Prepaid expenses and other current assets	116,948	130,336
Total current assets	2,294,945	2,195,190
Property and equipment, at cost:
Land	92,929	92,285
Buildings and improvements	617,071	606,168
Machinery and equipment	2,461,857	2,415,769
Construction in progress	94,027	103,058
Allowance for depreciation	(2,358,549)	(2,311,522)
Property, Plant and Equipment, Net, Total	907,335	905,758
Goodwill	147,047	142,742
Other intangible assets, net	73,072	69,754
Other assets	148,111	148,645
Total assets	3,570,510	3,462,089
Current liabilities:
Notes payable to banks	56	4
Trade accounts payable	191,935	222,373
Payroll and related expenses	136,386	135,702
Other accrued expenses	161,990	154,230
Income taxes	38,676	50,226
Total current liabilities	529,043	562,535
Long-term debt less current portion	406,385	370,470
U.S. transition tax payable	165,600	151,200
Deferred income taxes	342,207	336,465
Other liabilities	77,425	75,249
Accrued pension and other postretirement costs	283,754	281,701
Total liabilities	1,804,414	1,777,620
Redeemable convertible debentures	250,990	252,070
Vishay stockholders' equity
Common stock	13,212	13,188
Class B convertible common stock	1,210	1,213
Capital in excess of par value	1,753,762	1,752,506
(Accumulated deficit) retained earnings	(307,833)	(362,254)
Accumulated other comprehensive income (loss)	52,544	25,714
Total Vishay stockholders' equity	1,512,895	1,430,367
Noncontrolling interests	2,211	2,032
Total equity	1,515,106	1,432,399
Total liabilities, temporary equity, and equity	$ 3,570,510	$ 3,462,089

Consolidated Condensed Statemen

Consolidated Condensed Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Consolidated Condensed Statements of Operations [Abstract]
Net revenues	$ 716,795	$ 604,801
Costs of products sold	511,495	443,052
Gross profit	205,300	161,749
Selling, general, and administrative expenses	101,238	92,702
Restructuring and severance costs	0	1,469
Operating income	104,062	67,578
Other income (expense):
Interest expense	(7,677)	(6,790)
Other components of net periodic pension cost	(3,519)	(2,890)
Other	(847)	(396)
Loss on disposal of equity affiliate	0	(7,060)
Nonoperating Income (Expense), Total	(12,043)	(17,136)
Income before taxes	92,019	50,442
Income tax expense	29,474	13,493
Net earnings	62,545	36,949
Less: net earnings attributable to noncontrolling interests	179	230
Net earnings attributable to Vishay stockholders	$ 62,366	$ 36,719
Basic earnings per share attributable to Vishay stockholders	$ 0.43	$ 0.25
Diluted earnings per share attributable to Vishay stockholders	$ 0.39	$ 0.24
Weighted average shares outstanding - basic	144,327	146,274
Weighted average shares outstanding - diluted	159,502	154,876
Cash dividends per share	$ 0.0675	$ 0.0625

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Consolidated Statements of Comprehensive Income [Abstract]
Net earnings	$ 62,545	$ 36,949
Other comprehensive income (loss), net of tax
Pension and postretirement actuarial items	1,607	2,335
Foreign currency translation adjustment	27,024	17,293
Unrealized gain (loss) on available-for-sale securities	0	271
Other comprehensive income (loss)	28,631	19,899
Comprehensive income (loss)	91,176	56,848
Less: comprehensive income attributable to noncontrolling interests	179	230
Comprehensive income (loss) attributable to Vishay stockholders	$ 90,997	$ 56,618

Consolidated Condensed Stateme5

Consolidated Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Operating activities
Net earnings	$ 62,545	$ 36,949
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	40,558	40,212
(Gain) loss on disposal of property and equipment	(176)	60
Accretion of interest on convertible debentures	1,309	1,211
Inventory write-offs for obsolescence	5,457	4,834
Deferred income taxes	7,014	4,307
Non-cash loss on disposal of equity affiliate	0	7,060
Other	2,908	2,026
Net change in operating assets and liabilities, net of effects of businesses acquired	(72,756)	(52,985)
Net cash provided by operating activities	46,859	43,674
Investing activities
Capital expenditures	(28,273)	(16,668)
Proceeds from sale of property and equipment	184	943
Purchase of businesses, net of cash acquired	(12,072)	0
Purchase of short-term investments	(39,243)	(151,886)
Maturity of short-term investments	93,194	147,530
Other investing activities	(935)	(5,971)
Net cash provided by (used in) investing activities	12,855	(26,052)
Financing activities
Net proceeds (payments) on revolving credit lines	34,000	20,000
Net changes in short-term borrowings	52	8
Cash withholding taxes paid when shares withheld for vested equity awards	(2,297)	(1,971)
Other financing activities	0	(1,255)
Net cash provided by (used in) financing activities	22,020	7,646
Effect of exchange rate changes on cash and cash equivalents	9,825	2,337
Net increase (decrease) in cash and cash equivalents	91,559	27,605
Cash and cash equivalents at beginning of period	748,032	471,781
Cash and cash equivalents at end of period	839,591	499,386
Common Stock [Member]
Financing activities
Dividends and Interest Paid	(8,918)	(8,378)
Class B Convertible Common Stock [Member]
Financing activities
Dividends and Interest Paid	$ (817)	$ (758)

Consolidated Condensed Stateme6

Consolidated Condensed Statement of Equity - USD ($) $ in Thousands	Common Stock	Class B Convertible Common Stock [Member]	Capital In Excess of Par Value	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Total Vishay Stockholders' Equity	Noncontrolling Interest	Total
Cumulative effect of accounting change for adoption of ASU	$ 0	$ 0	$ 0	$ 2,210	$ 0	$ 2,210	$ 0	$ 2,210
Balance at December 31, 2017 at Dec. 31, 2015	13,546	1,213	2,058,492	(319,448)	(131,327)	1,622,476	5,567	1,628,043
Net earnings	0	0	0	48,792	0	48,792	581	49,373
Other comprehensive income (loss)	0	0	0	0	36,675	36,675	0	36,675
Distributions to noncontrolling interests	0	0	0	0	0	0	(707)	(707)
Share repurchase	(175)	0	(22,984)	0	0	(23,159)	0	(23,159)
Temporary equity reclassification	0	0	(88,659)	0	0	(88,659)	0	(88,659)
Restricted stock issuances	11	0	(553)	0	0	(542)	0	(542)
Dividends declared	0	0	36	(36,761)	0	(36,725)	0	(36,725)
Stock compensation expense	0	0	6,380	0	0	6,380	0	6,380
Stock options exercised	3	0	353	0	0	356	0	356
Tax effects of stock plan	0	0	(77)	0	0	(77)	0	(77)
Balance at Dec. 31, 2016	13,385	1,213	1,952,988	(305,207)	(94,652)	1,567,727	5,441	1,573,168
Cumulative effect of accounting change for adoption of ASU	0	0	0	386	0	386	0	386
Net earnings	0	0	0	(20,344)	0	(20,344)	784	(19,560)
Other comprehensive income (loss)	0	0	0	0	120,366	120,366	0	120,366
Distributions to noncontrolling interests	0	0	0	0	0	0	(1,140)	(1,140)
Acquisition of noncontrolling interests	0	0	(1,047)	0	0	(1,047)	(3,053)	(4,100)
Share repurchase	(225)	0	(39,719)	0	0	(39,944)	0	(39,944)
Temporary equity reclassification	0	0	(163,411)	0	0	(163,411)	0	(163,411)
Restricted stock issuances	20	0	(1,991)	0	0	(1,971)	0	(1,971)
Dividends declared	0	0	40	(37,089)	0	(37,049)	0	(37,049)
Stock compensation expense	0	0	4,394	0	0	4,394	0	4,394
Stock options exercised	8	0	1,252	0	0	1,260	0	1,260
Balance at Dec. 31, 2017	13,188	1,213	1,752,506	(362,254)	25,714	1,430,367	2,032	1,432,399
Cumulative effect of accounting change for adoption of ASU	0	0	0	1,801	(1,801)	0	0	0
Net earnings	0	0	0	62,366	0	62,366	179	62,545
Other comprehensive income (loss)	0	0	0	0	28,631	28,631	0	28,631
Conversions from Class B to common stock	3	(3)	0	0	0	0	0	0
Temporary equity reclassification	0	0	1,080	0	0	1,080	0	1,080
Restricted stock issuances	21	0	(2,318)	0	0	(2,297)	0	(2,297)
Dividends declared	0	0	11	(9,746)	0	(9,735)	0	(9,735)
Stock compensation expense	0	0	2,483	0	0	2,483	0	2,483
Balance at Mar. 31, 2018	$ 13,212	$ 1,210	$ 1,753,762	$ (307,833)	$ 52,544	$ 1,512,895	$ 2,211	$ 1,515,106

Consolidated Condensed Stateme7

Consolidated Condensed Statement of Equity (Parenthetical) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Condensed Statement of Equity [Abstract]
Restricted stock issuances (in shares)	211,328	200,688	110,825
Stock repurchase (in shares)		2,250,236	1,752,454
Stock options exercised (in shares)		77,334	27,619
Conversion of Class B shares	31,800
Common Stock, Dividends, Per Share, Cash Paid	$ 0.0675	$ 0.2550	$ 0.2500

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements [Abstract]
Basis of Presentation	Note 1 – Basis of Presentation The accompanying unaudited consolidated condensed financial statements of Vishay Intertechnology, Inc. ("Vishay" or the "Company") have been prepared in accordance with the instructions to Form 10-Q and therefore do not include all information and footnotes necessary for presentation of financial position, results of operations, and cash flows required by accounting principles generally accepted in the United States ("GAAP") for complete financial statements. The information furnished reflects all normal recurring adjustments which are, in the opinion of management, necessary for a fair summary of the financial position, results of operations, and cash flows for the interim periods presented. The financial statements should be read in conjunction with the consolidated financial statements filed with the Company's Annual Report on Form 10-K for the year ended December 31, 2017. The results of operations for the fiscal quarter ended March 31, 2018 are not necessarily indicative of the results to be expected for the full year. The Company reports interim financial information for 13-week periods beginning on a Sunday and ending on a Saturday, except for the first fiscal quarter, which always begins on January 1, and the fourth fiscal quarter, which always ends on December 31. The four fiscal quarters in 2018 end on March 31, 2018, June 30, 2018, September 29, 2018, and December 31, 2018, respectively. The four fiscal quarters in 2017 ended on April 1, 2017, July 1, 2017, September 30, 2017, and December 31, 2017, respectively. Recently Adopted Accounting Guidance In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities In March 2017, the FASB issued ASU No. 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost Recently Issued Accounting Guidance In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Changes in Accounting Policies Except for the changes described in "Recently Adopted Accounting Guidance" above and in this section below, the Company has consistently applied the accounting policies described in its Note 1 to its audited consolidated financial statement included in its annual report on Form 10-K for the year ended December 31, 2017, to all periods presented in these consolidated condensed financial statements. Revenue Recognition The Company adopted ASU 2014-09 as of January 1, 2018 using the full retrospective method. As a result, the Company has changed its accounting policy for revenue recognition. The details of significant changes and quantitative impact of the changes are disclosed below. Service-type warranty performance obligations ASU 2014-09 introduces the concept of service-type warranties, which represent separate performance obligations. Upon adoption of ASU No. 2014-09, the Company considers its warranty obligations as service-type warranties and allocates a portion of the estimated consideration to be received from the related contract to the service-type warranty performance obligation and recognizes the related revenue over the warranty period. The impact of accounting for service-type warranties as separate performance obligations was not significant in the retrospective adoption period and is included in the tables below. See further discussion of the warranty obligations in Note 2. Custom products The Company previously recognized revenue when the sales process was completed, which generally occurred when the product was delivered and risk of loss was transferred to the customer. Upon adoption of ASU 2014-09, the Company ASU 2014-09 provides several transition practical expedients. The Company has not restated completed contracts that begin and end in the same annual reporting period; used the transaction price at the date the contract was completed rather than estimating variable consideration amounts in the comparative reporting periods; has not disclosed the amount of the transaction price allocated to the remaining performance obligations and an explanation of when the Company expects to recognize the amount as revenue for the reporting periods presented prior to January 1, 2016; and has not retrospectively restated the contract for modifications made prior to January 1, 2016 and instead reflected the aggregate effect of all modifications when identifying the satisfied and unsatisfied performance obligations, determining the transaction price and allocating the transaction price pursuant to the transition practical expedients available. Pension and Other Postretirement Benefits The Company retrospectively adopted ASU 2017-07 as of January 1, 2018. As a result, the Company has changed its accounting policy for pension and other postretirement benefits costs as detailed below. ASU 2017-07 amends the income statement presentation requirements of net periodic benefit cost of defined benefit pension and other postretirement plans. The service cost component of net periodic pension cost is recorded in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period, and other components of net periodic pension cost are included on a separate line within other income (expense). The Company reclassified net benefit costs other than the current service component previously reported as cost of goods sold and selling, general, and administrative expenses to other expenses for each quarter in the retrospective adoption period in the table below. The Company also reclassified the $79,321 U.S. pension settlement charges recorded for the year ended December 31, 2016 to other expenses. See the impact of this change in the tables below. The retrospective adoption of ASUs 2014-09 and 2017-07 did not impact net earnings (loss) attributed to Vishay stockholders. See the combined impact of the retrospective adoption in the tables below: Fiscal quarters ended April 1, 2017 July 1, 2017 September 30, 2017 December 31, 2017 As Reported Adjustments Recast As Reported Adjustments Recast As Reported Adjustments Recast As Reported Adjustments Recast Net revenues $ 606,258 $ (1,457 ) $ 604,801 $ 644,892 $ (1,728 ) $ 643,164 $ 677,883 $ 58 $ 677,941 $ 674,489 $ (1,027 ) $ 673,462 Costs of products sold 445,383 (2,331 ) 443,052 471,929 (2,602 ) 469,327 488,610 (816 ) 487,794 497,988 (1,902 ) 496,086 Gross profit 160,875 874 161,749 172,963 874 173,837 189,273 874 190,147 176,501 875 177,376 Operating income 64,688 2,890 67,578 82,036 2,969 85,005 92,328 3,088 95,416 72,536 3,470 76,006 Total other income (expense) (14,246 ) (2,890 ) (17,136 ) (6,327 ) (2,969 ) (9,296 ) (6,140 ) (3,088 ) (9,228 ) (5,511 ) (3,470 ) (8,981 ) Income before taxes 50,442 - 50,442 75,709 - 75,709 86,188 - 86,188 67,025 - 67,025 Income tax expense 13,493 - 13,493 19,300 - 19,300 21,605 - 21,605 244,526 - 244,526 Net earnings (loss) 36,949 - 36,949 56,409 - 56,409 64,583 - 64,583 (177,501 ) - (177,501 ) Less: net earnings attributable to noncontrolling interests 230 - 230 219 - 219 179 - 179 156 - 156 Net earnings (loss) attributable to Vishay stockholders $ 36,719 $ - $ 36,719 $ 56,190 $ - $ 56,190 $ 64,404 $ - $ 64,404 $ (177,657 ) $ - $ (177,657 ) Years ended December 31, 2016 December 31, 2017 As Reported Adjustments Recast As Reported Adjustments Recast Net revenues $ 2,323,431 $ (6,103 ) $ 2,317,328 $ 2,603,522 $ (4,154 ) $ 2,599,368 Costs of products sold 1,753,648 (10,142 ) 1,743,506 1,903,910 (7,651 ) 1,896,259 Gross profit 569,783 4,039 573,822 699,612 3,497 703,109 Operating income 101,717 95,341 197,058 311,588 12,417 324,005 Total other income (expense) (7,501 ) (95,341 ) (102,842 ) (32,224 ) (12,417 ) (44,641 ) Income before taxes 94,216 - 94,216 279,364 - 279,364 Income tax expense 44,843 - 44,843 298,924 - 298,924 Net earnings (loss) 49,373 - 49,373 (19,560 ) - (19,560 ) Less: net earnings attributable to noncontrolling interests 581 - 581 784 - 784 Net earnings (loss) attributable to Vishay stockholders $ 48,792 $ - $ 48,792 $ (20,344 ) $ - $ (20,344 ) Reclassifications In addition to the changes due to the retrospective adoption of certain aspects of new accounting guidance described above, certain prior period amounts have been reclassified to conform to the current financial statement presentation.

Revenue Recognition Policies

Revenue Recognition Policies	3 Months Ended
	Mar. 31, 2018
Revenue Recognition [Abstract]
Revenue Recognition [Text Block]	Note 2 – Revenue Recognition As of January 1, 2018, the Company recognizes revenue from contracts with customers in accordance with ASU 2014-09. The Company has framework agreements with many of its customers that contain the terms and conditions of future sales, but do not create enforceable rights or obligations. Per ASU 2014-09, the Company's contracts are the combined purchase orders and the terms and conditions contained within such framework agreements. Payment terms for the Company's sales are generally less than sixty days. Substantially all of the Company's receivables are collected within twelve months of the transfer of products to the customer and the Company expects this to continue going forward. The Company applies the practical expedient within ASU 2014-09 to all of its contracts with payment terms less than or equal to twelve months and does not recognize a financing component of the transaction price. Revenue is measured based on the consideration specified in contracts with customers, and excludes any sales incentives and amounts collected on behalf of third parties. The Company recognizes revenue when it satisfies its performance obligations. The Company's contracts contain two performance obligations: delivery of products and warranty protection. The Company does not sell separate, enhanced, or extended warranty coverage, but through its customary business practices, the Company has created implied service-type warranties, which are accounted for as separate performance obligations. Revenue is allocated between these two performance obligations and recognized as the obligations are satisfied. The allocation of revenue to warranty protection is based on an estimate of expected cost plus margin. The delivery of products performance obligation is satisfied and product sales revenue is recognized when the customer takes control of the products. Warranty revenue is deferred and the warranty protection performance obligation is satisfied and revenue is recognized over the warranty period, which is typically less than twenty-four months from sale to end customer. The warranty deferred revenue liability is recorded within Other Accrued Expenses and Other Liabilities on the accompanying consolidated condensed balance sheets. The deferred revenue balance associated with the service-type warranty performance obligations and the components that comprise the change in the deferred revenue balance are not significant. The Company has and will continue to recognize revenue on sales to distributors when the distributor takes control of the products ("sold-to" model). The Company has agreements with distributors that allow distributors a limited credit for unsaleable products, which it terms a "scrap allowance." Consistent with industry practice, the Company also has a "stock, ship and debit" program whereby it considers requests by distributors for credits on previously purchased products that remain in distributors' inventory, to enable the distributors to offer more competitive pricing. In addition, the Company has contractual arrangements whereby it provides distributors with protection against price reductions initiated by the Company after product is sold by the Company to the distributor and prior to resale by the distributor. The Company recognizes the estimated variable consideration to be received as revenue and records a related accrued expense for the consideration not expected to be received, based upon its estimate of product returns, scrap allowances, "stock, ship and debit" credits, and price protection credits that will be attributable to sales recorded through the end of the period. The Company makes these estimates based upon sales levels to its distributors during the period, inventory levels at the distributors, current and projected market conditions, and historical experience under the programs. While the Company utilizes a number of different methodologies to estimate the accruals, all of the methodologies take into account sales levels to distributors during the relevant period, inventory levels at the distributors, current and projected market trends and conditions, recent and historical activity under the relevant programs, changes in program policies, and open requests for credits. These procedures require the exercise of significant judgments. The Company believes that it has a reasonable basis to estimate future credits under the programs. Distributor sales accrual activity is shown below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Beginning balance $ 36,680 $ 34,479 $ 34,479 $ 32,487 Sales allowances 24,188 21,520 89,009 86,896 Credits issued (28,450 ) (23,471 ) (87,403 ) (85,341 ) Foreign currency 288 (576 ) 595 437 Ending balance $ 32,706 $ 31,952 $ 36,680 $ 34,479 The Company pays commissions to external sales representatives on a per-sale basis. The Company applies the practical expedient available within ASU 2014-09 to all commissions paid as the future amortization period of the asset that the Company otherwise would have recognized is one year or less. Accordingly, these commissions are expensed as incurred. Internal staff are not paid commissions. The Company has elected to account for shipping and handling as activities to fulfill the promise to transfer the product even if the shipping and handling activities are performed after the customer obtains control. The Company does not evaluate whether shipping and handling activities are promised services to its customers. If control transfers and revenue is recognized for the related products before the shipping and handling activities occur, the related costs of those shipping and handling activities is accrued. The Company applies this accounting policy election consistently to similar types of transactions. See disaggregated revenue information in Note 10.

Acquisition Activities

Acquisition Activities	3 Months Ended
	Mar. 31, 2018
Acquisition and Divestiture Activities [Abstract]
Acquisition and Divestiture Activities	Note 3 – Acquisition Activities As part of its growth strategy, the Company seeks to expand through targeted acquisitions of other manufacturers of electronic components that have established positions in major markets, reputations for product quality and reliability, and product lines with which the Company has substantial marketing and technical expertise. On February 8, 2018, the Company acquired substantially all of the assets and liabilities of UltraSource, Inc., a U.S.-based, privately-held thin film circuit and thin film interconnect manufacturer, for $13,372, subject to customary post-closing adjustments. Based on an estimate of their fair values, the Company allocated $6,500 of the purchase price to definite-lived intangible assets. After allocating the purchase price to the assets acquired and liabilities assumed based on an estimation of their fair values at the date of acquisition, the Company recorded goodwill of $4,003 related to this acquisition. The results and operations of this acquisition have been included in the Resistors & Inductors segment since February 8, 2018. The inclusion of this acquisition did not have a material impact on the Company's consolidated results for the fiscal quarter ended March 31, 2018. The goodwill related to this acquisition is included in the Resistors & Inductors reporting unit for goodwill impairment testing. The preliminary allocation is pending finalization of a working capital adjustment. There can be no assurance that the estimated amounts recorded represent the final purchase allocation. Had this acquisition occurred as of the beginning of the periods presented in these consolidated condensed financial statements, the pro forma statements of operations would not be materially different than the consolidated condensed statements of operations presented. The remaining fluctuation in the goodwill account balance is due to foreign currency translation.

Restructuring and Related Activ

Restructuring and Related Activities	3 Months Ended
	Mar. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities	Note 4 – Restructuring and Related Activities The Company places a strong emphasis on controlling its costs and combats general price inflation by continuously improving its efficiency and operating performance. When the ongoing cost containment activities are not adequate, the Company takes actions to maintain its cost competitiveness. The Company incurred significant restructuring costs in its past to reduce its cost structure. Historically, the Company's primary cost reduction technique was through the transfer of production from high-labor-cost countries to lower-labor-cost countries. Since 2013, the Company's cost reduction programs have primarily focused on reducing fixed costs, including selling, general, and administrative expenses. As of December 31, 2017, the Company's restructuring programs were substantially completed. The following table summarizes restructuring and related expenses which were recognized and reported on a separate line in the accompanying consolidated condensed statements of operations: Fiscal quarter ended April 1, 2017 MOSFETs Enhanced Competitiveness Program $ 420 Global Cost Reduction Programs 1,049 Total $ 1,469 MOSFETs Enhanced Competitiveness Program Over a period of approximately 2 years and in a series of discrete steps, the manufacture of wafers for a substantial share of products was transferred into a more cost-efficient fab. As a consequence, certain other manufacturing previously occurring in-house was transferred to third-party foundries. This transfer of production was substantially completed by the end of the first fiscal quarter of 2016. As a result of a review of the financial results and outlook for the Company's MOSFETs segment following the completion of production transfers, the Company determined to implement further cost reductions for the MOSFETs segment. In November 2016, the Company announced an extension of the MOSFETs Enhanced Competitiveness Program. The revised program included various cost reduction initiatives, primarily the transfer of all remaining manufacturing operations at its Santa Clara, California facility to other Vishay facilities or third-party subcontractors. The following table summarizes the activity to date related to this program: Expense recorded in 2013 $ 2,328 Cash paid (267 ) Balance at December 31, 2013 $ 2,061 Expense recorded in 2014 6,025 Cash paid (856 ) Balance at December 31, 2014 $ 7,230 Expense recorded in 2015 5,367 Cash paid (426 ) Foreign currency translation 1 Balance at December 31, 2015 $ 12,172 Expense recorded in 2016 9,744 Cash paid (15,686 ) Foreign currency translation 2 Balance at December 31, 2016 $ 6,232 Expense recorded in 2017 3,204 Cash paid (7,173 ) Balance at December 31, 2017 $ 2,263 Cash paid (283 ) Balance at March 31, 2018 $ 1,980 Severance benefits are generally paid in a lump sum at cessation of employment. The entire liability is considered current and is included in other accrued expenses in the accompanying consolidated condensed balance sheets. Global Cost Reduction Programs The global cost reduction programs announced in 2015 included a plan to reduce selling, general, and administrative costs company-wide, and targeted streamlining and consolidation of production for certain product lines within its Capacitors and Resistors & Inductors segments. These programs were substantially implemented as of December 31, 2017. The following table summarizes the activity to date related to this program: Expense recorded in 2015 $ 13,753 Cash paid (986 ) Foreign currency translation (150 ) Balance at December 31, 2015 $ 12,617 Expense recorded in 2016 9,918 Cash paid (16,237 ) Foreign currency translation (34 ) Balance at December 31, 2016 $ 6,264 Expense recorded in 2017 8,069 Cash paid (7,168 ) Foreign currency translation 500 Balance at December 31, 2017 $ 7,665 Cash paid (1,027 ) Foreign currency translation 148 Balance at March 31, 2018 $ 6,786 The following table summarizes the expense recognized by segment related to this program: Fiscal quarter ended April 1, 2017 Resistors & Inductors $ 851 Capacitors 161 Unallocated Selling, General, and Administrative Expenses 37 Total $ 1,049 Severance benefits are generally paid in a lump sum at cessation of employment, though some are being paid in installments. The current portion of the liability is $4,222 and is included in other accrued expenses in the accompanying consolidated condensed balance sheets. The non-current portion of the liability is included in other liabilities in the accompanying consolidated condensed balance sheets.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Taxes [Abstract]
Income Taxes	Note 5 – Income Taxes The provision for income taxes consists of provisions for federal, state, and foreign income taxes. The effective tax rates for the periods ended March 31, 2018 and April 1, 2017 reflect the Company's expected tax rate on reported income from continuing operations before income tax and tax adjustments. The Company operates in a global environment with significant operations in various jurisdictions outside the United States. Accordingly, the consolidated income tax rate is a composite rate reflecting the Company's earnings and the applicable tax rates in the various jurisdictions where the Company operates. On December 22, 2017, the Tax Cuts and Jobs Act (the "TCJA") was enacted in the United States. The TCJA represents sweeping changes in U.S. tax law. Among the numerous changes in tax law, the TCJA permanently reduced the U.S. corporate income tax rate to 21% beginning in 2018; imposed a one-time transition tax on deferred foreign earnings; established a partial territorial tax system by allowing a 100% dividends received deduction on qualifying dividends paid by foreign subsidiaries; limited deductions for net interest expense; and expanded the U.S. taxation of foreign earned income to include "global intangible low-taxed income" ("GILTI") of foreign subsidiaries. The TCJA represents the first significant change in U.S. tax law in over 30 years. As permitted by SAB No. 118, the tax expense recorded in the fourth fiscal quarter of 2017 due to the enactment of the TCJA was considered "provisional," based on reasonable estimates. The Company is continuing to collect and analyze detailed information about the earnings and profits of its non-U.S. subsidiaries, the related taxes paid, the amounts which could be repatriated, the foreign taxes which may be incurred on repatriation, and the associated impact of these items under the TCJA. The Company may record adjustments to refine those estimates during the measurement period, as additional analysis is completed. No adjustments were recorded during the first fiscal quarter of 2018. Furthermore, the Company is continuing to evaluate the TCJA's provisions and may prospectively adjust its financial structure and business practices accordingly. The TCJA transitions the U.S. from a worldwide tax system to a partial territorial tax system. Under previous law, companies could indefinitely defer U.S. income taxation on unremitted foreign earnings. The TCJA imposes a one-time transition tax on deferred foreign earnings of 15.5% for liquid assets and 8% for illiquid assets, payable in defined increments over eight years. As a result of this requirement, the Company recognized provisional tax expense of $215,558 in 2017, and provisionally expects to pay $180,000, net of estimated applicable foreign tax credits, and after utilization of net operating loss, R&D credits, and foreign tax credit carryforwards. These previously deferred foreign earnings may now be repatriated to the United States without additional U.S. federal taxation. However, any such repatriation could incur withholding and other foreign taxes in the source and intervening foreign jurisdictions, and certain U.S. state taxes. Due to the changes in taxation of dividends received from foreign subsidiaries, and also because of the need to finance the payment of the transition tax, the Company made the determination during the fourth fiscal quarter of 2017 that certain unremitted foreign earnings in Israel, Germany, Austria, and France are no longer permanently reinvested, and recorded provisional tax expense of $213,000 to accrue the incremental foreign income taxes and withholding taxes payable to foreign jurisdictions assuming the hypothetical repatriation to the United States of these approximately $1,100,000 of available foreign earnings. Due to the existence of the foreign cash taxes payable at the source, the Company expects to actually repatriate these amounts at a measured pace over several years, and may decide to ultimately not repatriate some of these amounts. The Company terminated its previous cash repatriation program and recorded a provisional income tax benefit to reverse the associated deferred tax liability as a result of this planned repatriation. No amounts were repatriated pursuant to this program in the first fiscal quarter of 2018. The Company's effective tax rate for the period ended March 31, 2018 was negatively impacted by certain provisions of the TCJA. The provisions of the TCJA are interrelated and the impact of any specific provision cannot be isolated. The Company operates at a pre-tax loss in the U.S. and the reduction in the federal tax rate reduces the tax benefit recorded. In addition, the inclusion of GILTI income and the limitation and the deductibility of interest expense increased the effective tax rate. The Company has elected to account for GILTI tax in the period in which it is incurred, and therefore did not provide any deferred taxes in the consolidated financial statements at December 31, 2017. Income tax expense for the fiscal quarter ended March 31, 2018, includes tax expense of $1,316 for the periodic remeasurement of the deferred tax liability recorded for the foreign taxes associated with the cash repatriation program described above, primarily due to the foreign currency effects. Income tax expense for the fiscal quarter ended April 1, 2017 included a tax benefit of $968 for the periodic remeasurement of the deferred tax liability recorded for the cash repatriation program that was terminated as a result of the enactment of the TCJA. During the three fiscal months ended March 31, 2018, the liabilities for unrecognized tax benefits increased by $568 on a net basis, due to increases for tax positions taken in the current period, interest, and foreign currency effects.

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2018
Long-Term Debt [Abstract]
Long-Term Debt	Note 6 – Long-Term Debt Long-term debt consists of the following: March 31, 2018 December 31, 2017 Credit facility $ 184,000 $ 150,000 Convertible senior debentures, due 2040 111,157 110,412 Convertible senior debentures, due 2041 57,031 56,641 Convertible senior debentures, due 2042 62,853 62,518 Deferred financing costs (8,656 ) (9,101 ) 406,385 370,470 Less current portion - - $ 406,385 $ 370,470 Convertible Senior Debentures Vishay currently has three issuances of convertible senior debentures outstanding with generally congruent terms. The quarterly cash dividend program of the Company results in adjustments to the conversion rate and effective conversion price for each issuance of the Company's convertible senior debentures effective as of the ex-dividend date of each cash dividend. The following table summarizes some key facts and terms regarding the three series of outstanding convertible senior debentures following the adjustment made to the conversion rate of the debentures on the ex-dividend date of the March 29, 2018 dividend payment: Due 2040 Due 2041 Due 2042 Issuance date November 9, 2010 May 13, 2011 May 31, 2012 Maturity date November 15, 2040 May 15, 2041 June 1, 2042 Principal amount $ 275,000 $ 150,000 $ 150,000 Cash coupon rate (per annum) 2.25 % 2.25 % 2.25 % Nonconvertible debt borrowing rate at issuance (per annum) 8.00 % 8.375 % 7.50 % Conversion rate effective March 14, 2018 (per $1 principal amount) 77.4680 56.5321 91.0838 Effective conversion price effective March 14, 2018 (per share) $ 12.91 $ 17.69 $ 10.98 130% of the conversion price (per share) $ 16.78 $ 23.00 $ 14.27 Call date November 20, 2020 May 20, 2021 June 7, 2022 Prior to three months before the maturity date, the holders may only convert their debentures under the following circumstances: (1) during any fiscal quarter after the first full quarter subsequent to issuance, if the sale price of Vishay common stock reaches 130% of the conversion price for a specified period; (2) the trading price of the debentures falls below 98% of the product of the sale price of Vishay's common stock and the conversion rate for a specified period; (3) Vishay calls any or all of the debentures for redemption, at any time prior to the close of business on the third scheduled trading day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate events. The convertible debentures due 2042 became convertible subsequent to the December 31, 2016 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation, due to the sale price of Vishay's common stock exceeding 130% of the conversion price for the applicable periods. The convertible debentures due 2040 became convertible subsequent to the September 30, 2017 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation, due to the sale price of Vishay's common stock exceeding 130% of the conversion price for the applicable periods. The debentures due 2040 and due 2042 will remain convertible until June 30, 2018, at which time the conversion criteria will be reevaluated. At the direction of its Board of Directors, the Company intends, upon future conversion of any of the convertible senior debentures, to repay the principal amounts of the convertible senior debentures in cash and settle any additional amounts in shares of Vishay common stock. The excess of the amount that the Company would pay to the holders of the debentures due 2040 and due 2042 upon conversion over the carrying value of the liability component of the debentures currently convertible has been reclassified as temporary equity on the consolidated condensed financial statements. The Company intends to finance the principal amount of any converted debentures using borrowings under its credit facility. Accordingly, the debt component of the convertible debentures due 2040 and due 2042 continues to be classified as a non-current liability on the consolidated condensed balance sheets. GAAP requires an issuer to separately account for the liability and equity components of the instrument in a manner that reflects the issuer's nonconvertible debt borrowing rate when interest costs are recognized in subsequent periods. The resulting discount on the debt is amortized as non-cash interest expense in future periods. The carrying values of the liability and equity components of the convertible debentures are reflected in the Company's consolidated condensed balance sheets as follows: Principal amount of the debentures Unamortized discount Embedded derivative Carrying value of liability component Equity component (including temporary equity) - net carrying value March 31, 2018 Due 2040 $ 275,000 (164,143 ) 300 $ 111,157 $ 110,094 Due 2041 $ 150,000 (93,239 ) 270 $ 57,031 $ 62,246 Due 2042 $ 150,000 (87,276 ) 129 $ 62,853 $ 57,874 Total $ 575,000 $ (344,658 ) $ 699 $ 231,041 $ 230,214 December 31, 2017 Due 2040 $ 275,000 (164,794 ) 206 $ 110,412 $ 110,094 Due 2041 $ 150,000 (93,573 ) 214 $ 56,641 $ 62,246 Due 2042 $ 150,000 (87,600 ) 118 $ 62,518 $ 57,874 Total $ 575,000 $ (345,967 ) $ 538 $ 229,571 $ 230,214 Interest is payable on the debentures semi-annually at the cash coupon rate; however, the remaining debt discount is being amortized as additional non-cash interest expense using an effective annual interest rate equal to the Company's estimated nonconvertible debt borrowing rate at the time of issuance. In addition to ordinary interest, contingent interest will accrue in certain circumstances relating to the trading price of the debentures and under certain other circumstances beginning ten years subsequent to issuance. Interest expense related to the debentures is reflected on the consolidated condensed statements of operations for the fiscal quarters ended: Contractual coupon interest Non-cash amortization of debt discount Non-cash amortization of deferred financing costs Non-cash change in value of derivative liability Total interest expense related to the debentures March 31, 2018 Due 2040 $ 1,547 651 22 94 $ 2,314 Due 2041 $ 844 334 12 56 $ 1,246 Due 2042 $ 844 324 13 11 $ 1,192 Total $ 3,235 $ 1,309 $ 47 $ 161 $ 4,752 April 1, 2017 Due 2040 $ 1,547 602 22 (25 ) $ 2,146 Due 2041 $ 844 308 12 2 $ 1,166 Due 2042 $ 844 301 13 (4 ) $ 1,154 Total $ 3,235 $ 1,211 $ 47 $ (27 ) $ 4,466

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Abstract]
Accumulated Other Comprehensive Income (Loss)	Note 7 – Accumulated Other Comprehensive Income (Loss) The cumulative balance of each component of other comprehensive income (loss) and the income tax effects allocated to each component are as follows: Pension and other post-retirement actuarial items Currency translation adjustment Unrealized gain (loss) on available-for-sale securities Total Balance at January 1, 2018 $ (69,041 ) $ 92,954 $ 1,801 $ 25,714 Cumulative effect of accounting for adoption of ASU 2016-01 - - (1,801 ) $ (1,801 ) Other comprehensive income before reclassifications - 27,024 - $ 27,024 Tax effect - - - $ - Other comprehensive income before reclassifications, net of tax - 27,024 - $ 27,024 Amounts reclassified out of AOCI 2,296 - - $ 2,296 Tax effect (689 ) - - $ (689 ) Amounts reclassified out of AOCI, net of tax 1,607 - - $ 1,607 Net other comprehensive income $ 1,607 $ 27,024 $ - $ 28,631 Balance at March 31, 2018 $ (67,434 ) $ 119,978 $ - $ 52,544 The Company recognized a cumulative-effect adjustment to retained earnings (accumulated deficit) of $1,801 for the cumulative change in fair value of available-for-sale equity investments previously recognized in other comprehensive income due to the adoption of ASU 2016-01. See Note 1 for further information. Reclassifications of pension and other post-retirement actuarial items out of AOCI are included in the computation of net periodic benefit cost. See Note 8 for further information.

Pensions and Other Postretireme

Pensions and Other Postretirement Benefits	3 Months Ended
	Mar. 31, 2018
Pensions and Other Postretirement Benefits [Abstract]
Pensions and Other Postretirement Benefits	Note 8 – Pensions and Other Postretirement Benefits The Company maintains various retirement benefit plans. Defined Benefit Pension Plans The following table shows the components of the net periodic pension cost for the first fiscal quarters of 2018 and 2017 for the Company's defined benefit pension plans: Fiscal quarter ended March 31, 2018 Fiscal quarter ended April 1, 2017 U.S. Plans Non-U.S. Plans U.S. Plans Non-U.S. Plans Net service cost $ - $ 948 $ - $ 903 Interest cost 371 1,242 410 1,167 Expected return on plan assets - (488 ) - (506 ) Amortization of prior service cost 36 55 36 18 Amortization of losses 159 1,604 82 1,478 Curtailment and settlement losses - 462 - 322 Net periodic benefit cost $ 566 $ 3,823 $ 528 $ 3,382 Other Postretirement Benefits The following table shows the components of the net periodic benefit cost for the first fiscal quarters of 2018 and 2017 for the Company's other postretirement benefit plans: Fiscal quarter ended March 31, 2018 Fiscal quarter ended April 1, 2017 U.S. Plans Non-U.S. Plans U.S. Plans Non-U.S. Plans Service cost $ 34 $ 75 $ 33 $ 64 Interest cost 68 30 77 24 Amortization of prior service (credit) (37 ) - (209 ) - Amortization of losses (gains) (10 ) 27 (23 ) 14 Net periodic benefit cost $ 55 $ 132 $ (122 ) $ 102

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2018
Stock-Based Compensation [Abstract]
Stock-Based Compensation	Note 9 – Stock-Based Compensation The Company has various stockholder-approved programs which allow for the grant of stock-based compensation to officers, employees, and non-employee directors of the Company. The amount of compensation cost related to stock-based payment transactions is measured based on the grant-date fair value of the equity instruments issued. The Company determines compensation cost for restricted stock units ("RSUs") and phantom stock units based on the grant-date fair value of the underlying common stock adjusted for expected dividends paid over the required vesting period for non-participating awards. Compensation cost is recognized over the period that an officer, employee, or non-employee director provides service in exchange for the award. The following table summarizes stock-based compensation expense recognized: Fiscal quarters ended March 31, 2018 April 1, 2017 Restricted stock units $ 2,269 $ 2,204 Phantom stock units 214 163 Total $ 2,483 $ 2,367 The Company recognizes compensation cost for RSUs that are expected to vest and records cumulative adjustments in the period that the expectation changes. The following table summarizes unrecognized compensation cost and the weighted average remaining amortization periods at March 31, 2018 (amortization periods in years) Unrecognized Compensation Cost Weighted Average Remaining Amortization Periods Restricted stock units $ 5,394 1.7 Phantom stock units - 0.0 Total $ 5,394 The Company currently expects all performance-based RSUs to vest and all of the associated unrecognized compensation cost for performance-based RSUs presented in the table above to be recognized. 2007 Stock Incentive Plan The Company's 2007 Stock Incentive Program (the "2007 Program"), as amended and restated, permits the grant of up to 6,500,000 shares of restricted stock, unrestricted stock, RSUs, stock options, and phantom stock units, to officers, employees, and non-employee directors of the Company. Such instruments are available for grant until May 20, 2024. Restricted Stock Units RSU activity under the 2007 Program as of March 31, 2018 and changes during the three fiscal months then ended are presented below (number of RSUs in thousands) Number of RSUs Weighted Average Grant-date Fair Value per Unit Outstanding: January 1, 2018 986 $ 13.34 Granted 252 18.90 Vested* (334 ) 13.67 Cancelled or forfeited - - Outstanding at March 31, 2018 904 $ 14.77 Expected to vest at March 31, 2018 904 * The number of RSUs vested includes shares that the Company withheld on behalf of employees to satisfy the statutory tax withholding requirements. The number of performance-based RSUs that are scheduled to vest increases ratably based on the achievement of defined performance criteria between the established target and maximum levels. RSUs with performance-based vesting criteria are expected to vest as follows (number of RSUs in thousands) Vesting Date Expected to Vest Not Expected to Vest Total January 1, 2019 213 - 213 January 1, 2020 167 - 167 January 1, 2021 141 - 141 Phantom Stock Units The 2007 Program authorizes the grant of phantom stock units to the extent provided for in the Company's employment agreements with certain executives. Each phantom stock unit entitles the recipient to receive a share of common stock at the individual's termination of employment or any other future date specified in the applicable employment agreement. Phantom stock units participate in dividend distribution on the same basis as the Company's common stock and Class B common stock. Dividend equivalents are issued in the form of additional units of phantom stock. The phantom stock units are fully vested at all times. Phantom stock unit activity under the phantom stock plan as of March 31, 2018 and changes during the three fiscal months then ended are presented below (number of phantom stock units in thousands) Number of units Grant-date Fair Value per Unit Outstanding: January 1, 2018 157 Granted 10 $ 21.35 Dividend equivalents issued 1 Outstanding at March 31, 2018 168

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2018
Segment Information [Abstract]
Segment Information	Note 10 – Segment Information Vishay is a global manufacturer and supplier of electronic components. Vishay operates, and its chief operating decision maker makes strategic and operating decisions with regards to assessing performance and allocating resources based on, five reporting segments: MOSFETs, Diodes, Optoelectronic Components, Resistors & Inductors, and Capacitors. These segments represent groupings of product lines based on their functionality: ● Metal oxide semiconductor field-effect transistors ("MOSFETs") function as solid-state switches to control power. ● Diodes route, regulate, and block radio frequency, analog, and power signals; protect systems from surges or electrostatic discharge damage; or provide electromagnetic interference filtering. ● Optoelectronic components emit light, detect light, or do both. ● Resistors and inductors both impede electric current. Resistors are basic components used in all forms of electronic circuitry to adjust and regulate levels of voltage and current. Inductors use an internal magnetic field to change alternating current phase and resist alternating current. ● Capacitors store energy and discharge it when needed. Vishay's reporting segments generate substantially all of their revenue from product sales to the industrial, automotive, telecommunications, computing, consumer products, power supplies, military and aerospace, and medical end markets. A small portion of revenues is from royalties. The Company evaluates business segment performance on operating income, exclusive of certain items ("segment operating income"). Only dedicated, direct selling, general, and administrative expenses of the segments are included in the calculation of segment operating income. The Company's calculation of segment operating income excludes such selling, general, and administrative costs as global operations, sales and marketing, information systems, finance and administration groups, as well as restructuring and severance costs, goodwill and long-lived asset impairment charges, and other items. Management believes that evaluating segment performance excluding such items is meaningful because it provides insight with respect to intrinsic operating results of the Company. These items represent reconciling items between segment operating income and consolidated operating income. Business segment assets are the owned or allocated assets used by each business. The Company also regularly evaluates gross profit by segment to assist in the analysis of consolidated gross profit. The Company considers segment operating income to be the more important metric because it more fully captures the business operations of the segments. The following tables set forth business segment information: MOSFETs Diodes Optoelectronic Components Resistors & Inductors Capacitors Total Fiscal quarter ended March 31, 2018: Product Sales $ 127,494 $ 167,017 $ 71,958 $ 244,019 $ 106,268 $ 716,756 Royalty Revenues 12 - - 27 - $ 39 Total Revenue $ 127,506 $ 167,017 $ 71,958 $ 244,046 $ 106,268 $ 716,795 Gross Profit $ 32,022 $ 43,200 $ 27,233 $ 78,530 $ 24,315 $ 205,300 Segment Operating Income $ 22,558 $ 37,931 $ 22,794 $ 70,002 $ 18,893 $ 172,178 Fiscal quarter ended April 1, 2017:* Product Sales $ 104,842 $ 144,585 $ 65,262 $ 200,246 $ 89,860 $ 604,795 Royalty Revenues - - - 6 - $ 6 Total Revenue $ 104,842 $ 144,585 $ 65,262 $ 200,252 $ 89,860 $ 604,801 Gross Profit $ 20,717 $ 38,162 $ 22,442 $ 61,215 $ 19,213 $ 161,749 Segment Operating Income $ 11,803 $ 33,442 $ 17,117 $ 53,958 $ 14,190 $ 130,510 *Recast for the retrospective adoption of ASUs 2014-09 and 2017-07. See Note 1. Fiscal quarters ended March 31, 2018 April 1, 2017*** Reconciliation: Segment Operating Income $ 172,178 $ 130,510 Restructuring and Severance Costs - (1,469 ) Unallocated Selling, General, and Administrative Expenses (68,116 ) (61,463 ) Consolidated Operating Income 104,062 $ 67,578 Unallocated Other Income (Expense) (12,043 ) (17,136 ) Consolidated Income Before Taxes $ 92,019 50,442 ***Recast for the adoption of ASU 2017-07. See Note 1. The Company has a broad line of products that it sells to OEMs, EMS companies, and independent distributors. The distribution of sales by customer type is shown below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Distributors $ 404,060 $ 345,703 $ 1,484,276 $ 1,280,060 OEMs 264,050 214,647 931,291 861,322 EMS companies 48,685 44,451 183,801 175,946 Total Revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328 Net revenues were attributable to customers in the following regions: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Asia $ 285,478 $ 257,058 $ 1,091,107 $ 948,195 Europe 267,382 206,025 902,357 810,543 Americas 163,935 141,718 605,904 558,590 Total Revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328 The Company generates substantially all of its revenue from product sales to end customers in the industrial, automotive, telecommunications, computing, consumer products, power supplies, military and aerospace, and medical end markets. Sales by end market are presented below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Industrial $ 280,212 $ 216,766 $ 934,631 $ 796,031 Automotive 208,394 175,343 727,220 640,767 Telecommunications 45,924 45,835 190,682 193,456 Computing 47,431 41,070 198,850 172,481 Consumer Products 37,259 29,607 145,243 150,741 Power Supplies 34,243 34,858 160,038 132,555 Military and Aerospace 35,214 33,176 132,898 128,523 Medical 28,118 28,146 109,806 102,774 Total revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Note 11 – Earnings Per Share The following table sets forth the computation of basic and diluted earnings per share attributable to Vishay stockholders (shares in thousands) Fiscal quarters ended March 31, 2018 April 1, 2017 Numerator: Net earnings attributable to Vishay stockholders $ 62,366 $ 36,719 Denominator: Denominator for basic earnings per share: Weighted average shares 144,160 146,120 Outstanding phantom stock units 167 154 Adjusted weighted average shares - basic 144,327 146,274 Effect of dilutive securities: Convertible and exchangeable debt instruments 14,610 8,349 Restricted stock units 565 253 Dilutive potential common shares 15,175 8,602 Denominator for diluted earnings per share: Adjusted weighted average shares - diluted 159,502 154,876 Basic earnings per share attributable to Vishay stockholders $ 0.43 $ 0.25 Diluted earnings per share attributable to Vishay stockholders $ 0.39 $ 0.24 Diluted earnings per share for the periods presented do not reflect the following weighted average potential common shares that would have an antidilutive effect or have unsatisfied performance conditions (in thousands) Fiscal quarters ended March 31, 2018 April 1, 2017 Convertible and exchangeable notes: Convertible Senior Debentures, due 2041 - 8,340 Weighted average other 307 581 In periods in which they are dilutive, if the potential common shares related to the exchangeable notes are included in the computation, the related interest savings, net of tax, assuming conversion/exchange is added to the net earnings used to compute earnings per share. The Company's convertible debt instruments are only convertible for specified periods upon the occurrence of certain events. The convertible debentures due 2042 became convertible subsequent to the December 31, 2016 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation. The convertible debentures due 2040 became convertible subsequent to the September 30, 2017 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation. At the direction of its Board of Directors, the Company intends, upon conversion, to repay the principal amounts of the convertible senior debentures, due 2040, due 2041, and due 2042, in cash and settle any additional amounts in shares of Vishay common stock. Accordingly, the debentures are included in the diluted earnings per share computation using the "treasury stock method" (similar to options and warrants) rather than the "if converted method" otherwise required for convertible debt. Under the "treasury stock method," Vishay calculates the number of shares issuable under the terms of the debentures based on the average market price of Vishay common stock during the period, and that number is included in the total diluted shares figure for the period. If the average market price is less than $12.91, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2040, if the average market price is less than $17.69, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2041, and if the average market price is less than $10.98, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2042.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Measurements [Abstract]
Fair Value Measurements	Note 12 – Fair Value Measurements The fair value measurement accounting guidance establishes a valuation hierarchy of the inputs used to measure fair value. This hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The following is a brief description of those three levels: Level 1: Observable inputs such as quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2: Inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3: Unobservable inputs that reflect the Company's own assumptions. An asset or liability's classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement. There have been no changes in the classification of any financial instruments within the fair value hierarchy in the periods presented. The following table provides the financial assets and liabilities carried at fair value measured on a recurring basis: Total Fair Value Level 1 Level 2 Level 3 March 31, 2018 Assets: Assets held in rabbi trusts $ 43,756 $ 27,199 $ 16,557 $ - Available for sale securities $ 4,702 4,702 - - $ 48,458 $ 31,901 $ 16,557 $ - Liabilities: Embedded derivative - convertible debentures due 2040 $ (300 ) $ - $ - $ (300 ) Embedded derivative - convertible debentures due 2041 $ (270 ) - - (270 ) Embedded derivative - convertible debentures due 2042 $ (129 ) - - (129 ) $ (699 ) $ - $ - $ (699 ) December 31, 2017 Assets: Assets held in rabbi trusts $ 45,252 $ 28,589 16,663 $ - Available for sale securities $ 4,621 4,621 - - $ 49,873 $ 33,210 $ 16,663 $ - Liabilities: Embedded derivative - convertible debentures due 2040 $ (206 ) $ - $ - $ (206 ) Embedded derivative - convertible debentures due 2041 $ (214 ) - - (214 ) Embedded derivative - convertible debentures due 2042 $ (118 ) - - (118 ) $ (538 ) $ - $ - $ (538 ) The Company maintains non-qualified trusts, referred to as "rabbi" trusts, to fund payments under deferred compensation and non-qualified pension plans. Rabbi trust assets consist primarily of marketable securities, classified as available-for-sale and company-owned life insurance assets. The marketable securities held in the rabbi trusts are valued using quoted market prices on the last business day of the period. The company-owned life insurance assets are valued in consultation with the Company's insurance brokers using the value of underlying assets of the insurance contracts. The fair value measurement of the marketable securities held in the rabbi trust is considered a Level 1 measurement and the measurement of the company-owned life insurance assets is considered a Level 2 measurement within the fair value hierarchy. The Company holds investments in equity securities that are intended to fund a portion of its pension and other postretirement benefit obligations outside of the United States. The investments are valued based on quoted market prices on the last business day of the period. The fair value measurement of the investments is considered a Level 1 measurement within the fair value hierarchy. The convertible senior debentures, due 2040, due 2041, and due 2042, issued by the Company on November 9, 2010, May 13, 2011, and May 31, 2012, respectively, contain embedded derivative features that GAAP requires to be bifurcated and remeasured each reporting period. Each quarter, the change in the fair value of the embedded derivative features, if any, is recorded in the consolidated condensed statements of operations. The Company uses a derivative valuation model to derive the value of the embedded derivative features. Key inputs into this valuation model are the Company's current stock price, risk-free interest rates, the stock dividend yield, the stock volatility, and the debentures' credit spread over LIBOR. The first three aforementioned inputs are based on observable market data and are considered Level 2 inputs while the last two aforementioned inputs are unobservable and thus require management's judgment and are considered Level 3 inputs. The fair value measurement is considered a Level 3 measurement within the fair value hierarchy. The Company enters into forward contracts with highly-rated financial institutions to mitigate the foreign currency risk associated with intercompany loans denominated in a currency other than the legal entity's functional currency. The notional amount of the forward contracts was $100,000 and $100,000 as of March 31, 2018 and December 31, 2017, respectively. The forward contracts are short-term in nature and are expected to be renewed at the Company's discretion until the intercompany loans are repaid. We have not designated the forward contracts as hedges for accounting purposes, and as such the change in the fair value of the contracts is recognized in the consolidated condensed statements of operations as a component of other income (expense). The Company estimates the fair value of the forward contracts based on applicable and commonly used pricing models using current market information and is considered a Level 2 measurement within the fair value hierarchy. The value of the forward contracts was immaterial as of March 31, 2018. The Company does not utilize derivatives or other financial instruments for trading or other speculative purposes. The fair value of the long-term debt, excluding the derivative liabilities and deferred financing costs, at March 31, 2018 and December 31, 2017 is approximately $1,015,400 and $1,071,200, respectively, compared to its carrying value, excluding the derivative liabilities and deferred financing costs, of $414,342 and $379,033, respectively. The Company estimates the fair value of its long-term debt using a combination of quoted market prices for similar financing arrangements and expected future payments discounted at risk-adjusted rates, which are considered Level 2 inputs. At March 31, 2018 and December 31, 2017, the Company's short-term investments were comprised of time deposits with financial institutions that have maturities that exceed 90 days from the date of acquisition; however they all mature within one year from the respective balance sheet dates. The Company's short-term investments are accounted for as held-to-maturity debt instruments, at amortized cost, which approximates their fair value. The investments are funded with excess cash not expected to be needed for operations prior to maturity; therefore, the Company believes it has the intent and ability to hold the short-term investments until maturity. At each reporting date, the Company performs an evaluation to determine if any unrealized losses are other-than-temporary. No other-than-temporary impairments have been recognized on these securities, and there are no unrecognized holding gains or losses for these securities during the periods presented. There have been no transfers to or from the held-to-maturity classification. All decreases in the account balance are due to returns of principal at the securities' maturity dates. Interest on the securities is recognized as interest income when earned. At March 31, 2018 and December 31, 2017, the Company's cash and cash equivalents were comprised of demand deposits, time deposits with maturities of three months or less when purchased, and money market funds. The Company estimates the fair value of its cash, cash equivalents, and short-term investments using level 2 inputs. Based on the current interest rates for similar investments with comparable credit risk and time to maturity, the fair value of the Company's cash, cash equivalents, and held-to-maturity short-term investments approximate the carrying amounts reported in the consolidated condensed balance sheets. The Company's financial instruments also include accounts receivable, short-term notes payable, and accounts payable. The carrying amounts for these financial instruments reported in the consolidated condensed balance sheets approximate their fair values.

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements [Abstract]
Fiscal Period, Policy	The Company reports interim financial information for 13-week periods beginning on a Sunday and ending on a Saturday, except for the first fiscal quarter, which always begins on January 1, and the fourth fiscal quarter, which always ends on December 31. The four fiscal quarters in 2018 end on March 31, 2018, June 30, 2018, September 29, 2018, and December 31, 2018, respectively. The four fiscal quarters in 2017 ended on April 1, 2017, July 1, 2017, September 30, 2017, and December 31, 2017, respectively.
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	Recently Issued Accounting Guidance In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Recently Adopted Accounting Guidance In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities In March 2017, the FASB issued ASU No. 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost

Income Taxes (Policies)

Income Taxes (Policies)	3 Months Ended
	Mar. 31, 2018
Income Taxes [Abstract]
Effective Income tax Rate Description	The provision for income taxes consists of provisions for federal, state, and foreign income taxes. The effective tax rates for the periods ended March 31, 2018 and April 1, 2017 reflect the Company's expected tax rate on reported income from continuing operations before income tax and tax adjustments. The Company operates in a global environment with significant operations in various jurisdictions outside the United States. Accordingly, the consolidated income tax rate is a composite rate reflecting the Company's earnings and the applicable tax rates in the various jurisdictions where the Company operates.

Stock-Based Compensation (Polic

Stock-Based Compensation (Policies)	3 Months Ended
	Mar. 31, 2018
Stock-Based Compensation [Abstract]
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	The amount of compensation cost related to stock-based payment transactions is measured based on the grant-date fair value of the equity instruments issued. The Company determines compensation cost for restricted stock units ("RSUs") and phantom stock units based on the grant-date fair value of the underlying common stock adjusted for expected dividends paid over the required vesting period for non-participating awards. Compensation cost is recognized over the period that an officer, employee, or non-employee director provides service in exchange for the award.

Segment Information (Policies)

Segment Information (Policies)	3 Months Ended
	Mar. 31, 2018
Segment Information [Abstract]
Segment Reporting, Policy [Policy Text Block]	Vishay is a global manufacturer and supplier of electronic components. Vishay operates, and its chief operating decision maker makes strategic and operating decisions with regards to assessing performance and allocating resources based on, five reporting segments: MOSFETs, Diodes, Optoelectronic Components, Resistors & Inductors, and Capacitors. These segments represent groupings of product lines based on their functionality: ● Metal oxide semiconductor field-effect transistors ("MOSFETs") function as solid-state switches to control power. ● Diodes route, regulate, and block radio frequency, analog, and power signals; protect systems from surges or electrostatic discharge damage; or provide electromagnetic interference filtering. ● Optoelectronic components emit light, detect light, or do both. ● Resistors and inductors both impede electric current. Resistors are basic components used in all forms of electronic circuitry to adjust and regulate levels of voltage and current. Inductors use an internal magnetic field to change alternating current phase and resist alternating current. ● Capacitors store energy and discharge it when needed. Vishay's reporting segments generate substantially all of their revenue from product sales to the industrial, automotive, telecommunications, computing, consumer products, power supplies, military and aerospace, and medical end markets. A small portion of revenues is from royalties. The Company evaluates business segment performance on operating income, exclusive of certain items ("segment operating income"). Only dedicated, direct selling, general, and administrative expenses of the segments are included in the calculation of segment operating income. The Company's calculation of segment operating income excludes such selling, general, and administrative costs as global operations, sales and marketing, information systems, finance and administration groups, as well as restructuring and severance costs, goodwill and long-lived asset impairment charges, and other items. Management believes that evaluating segment performance excluding such items is meaningful because it provides insight with respect to intrinsic operating results of the Company. These items represent reconciling items between segment operating income and consolidated operating income. Business segment assets are the owned or allocated assets used by each business. The Company also regularly evaluates gross profit by segment to assist in the analysis of consolidated gross profit. The Company considers segment operating income to be the more important metric because it more fully captures the business operations of the segments.

Earnings Per Share (Policies)

Earnings Per Share (Policies)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Discussion on convertible debt included in computation of earnings per share diluted	The Company's convertible debt instruments are only convertible for specified periods upon the occurrence of certain events. The convertible debentures due 2042 became convertible subsequent to the December 31, 2016 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation. The convertible debentures due 2040 became convertible subsequent to the September 30, 2017 evaluation of the conversion criteria, and have remained convertible for each subsequent quarterly evaluation through the March 31, 2018 evaluation. At the direction of its Board of Directors, the Company intends, upon conversion, to repay the principal amounts of the convertible senior debentures, due 2040, due 2041, and due 2042, in cash and settle any additional amounts in shares of Vishay common stock. Accordingly, the debentures are included in the diluted earnings per share computation using the "treasury stock method" (similar to options and warrants) rather than the "if converted method" otherwise required for convertible debt. Under the "treasury stock method," Vishay calculates the number of shares issuable under the terms of the debentures based on the average market price of Vishay common stock during the period, and that number is included in the total diluted shares figure for the period. If the average market price is less than $12.91, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2040, if the average market price is less than $17.69, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2041, and if the average market price is less than $10.98, no shares are included in the diluted earnings per share computation for the convertible senior debentures due 2042.

Fair Value Measurements (Polici

Fair Value Measurements (Policies)	3 Months Ended
	Mar. 31, 2018
Fair Value Measurements [Abstract]
Fair Value of Financial Instruments, Policy	The fair value measurement accounting guidance establishes a valuation hierarchy of the inputs used to measure fair value. This hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The following is a brief description of those three levels: Level 1: Observable inputs such as quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2: Inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3: Unobservable inputs that reflect the Company's own assumptions. An asset or liability's classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement. There have been no changes in the classification of any financial instruments within the fair value hierarchy in the periods presented.

Basis of Presentation (Tables)

Basis of Presentation (Tables)	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements [Abstract]
Schedule of Retrospective Adoption of New Accounting Pronouncements [Table Text Block]	The retrospective adoption of ASUs 2014-09 and 2017-07 did not impact net earnings (loss) attributed to Vishay stockholders. See the combined impact of the retrospective adoption in the tables below: Fiscal quarters ended April 1, 2017 July 1, 2017 September 30, 2017 December 31, 2017 As Reported Adjustments Recast As Reported Adjustments Recast As Reported Adjustments Recast As Reported Adjustments Recast Net revenues $ 606,258 $ (1,457 ) $ 604,801 $ 644,892 $ (1,728 ) $ 643,164 $ 677,883 $ 58 $ 677,941 $ 674,489 $ (1,027 ) $ 673,462 Costs of products sold 445,383 (2,331 ) 443,052 471,929 (2,602 ) 469,327 488,610 (816 ) 487,794 497,988 (1,902 ) 496,086 Gross profit 160,875 874 161,749 172,963 874 173,837 189,273 874 190,147 176,501 875 177,376 Operating income 64,688 2,890 67,578 82,036 2,969 85,005 92,328 3,088 95,416 72,536 3,470 76,006 Total other income (expense) (14,246 ) (2,890 ) (17,136 ) (6,327 ) (2,969 ) (9,296 ) (6,140 ) (3,088 ) (9,228 ) (5,511 ) (3,470 ) (8,981 ) Income before taxes 50,442 - 50,442 75,709 - 75,709 86,188 - 86,188 67,025 - 67,025 Income tax expense 13,493 - 13,493 19,300 - 19,300 21,605 - 21,605 244,526 - 244,526 Net earnings (loss) 36,949 - 36,949 56,409 - 56,409 64,583 - 64,583 (177,501 ) - (177,501 ) Less: net earnings attributable to noncontrolling interests 230 - 230 219 - 219 179 - 179 156 - 156 Net earnings (loss) attributable to Vishay stockholders $ 36,719 $ - $ 36,719 $ 56,190 $ - $ 56,190 $ 64,404 $ - $ 64,404 $ (177,657 ) $ - $ (177,657 ) Years ended December 31, 2016 December 31, 2017 As Reported Adjustments Recast As Reported Adjustments Recast Net revenues $ 2,323,431 $ (6,103 ) $ 2,317,328 $ 2,603,522 $ (4,154 ) $ 2,599,368 Costs of products sold 1,753,648 (10,142 ) 1,743,506 1,903,910 (7,651 ) 1,896,259 Gross profit 569,783 4,039 573,822 699,612 3,497 703,109 Operating income 101,717 95,341 197,058 311,588 12,417 324,005 Total other income (expense) (7,501 ) (95,341 ) (102,842 ) (32,224 ) (12,417 ) (44,641 ) Income before taxes 94,216 - 94,216 279,364 - 279,364 Income tax expense 44,843 - 44,843 298,924 - 298,924 Net earnings (loss) 49,373 - 49,373 (19,560 ) - (19,560 ) Less: net earnings attributable to noncontrolling interests 581 - 581 784 - 784 Net earnings (loss) attributable to Vishay stockholders $ 48,792 $ - $ 48,792 $ (20,344 ) $ - $ (20,344 )

Revenue Recognition Policies (T

Revenue Recognition Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue Recognition Policies
Schedule of Loss Contingencies by Contingency [Table Text Block]	Distributor sales accrual activity is shown below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Beginning balance $ 36,680 $ 34,479 $ 34,479 $ 32,487 Sales allowances 24,188 21,520 89,009 86,896 Credits issued (28,450 ) (23,471 ) (87,403 ) (85,341 ) Foreign currency 288 (576 ) 595 437 Ending balance $ 32,706 $ 31,952 $ 36,680 $ 34,479

Restructuring and Related Act28

Restructuring and Related Activities (Tables)	3 Months Ended
	Mar. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring and Related Expenses	The following table summarizes restructuring and related expenses which were recognized and reported on a separate line in the accompanying consolidated condensed statements of operations: Fiscal quarter ended April 1, 2017 MOSFETs Enhanced Competitiveness Program $ 420 Global Cost Reduction Programs 1,049 Total $ 1,469
MOSFETs Enhanced Competitiveness Program [Member]
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	The following table summarizes the activity to date related to this program: Expense recorded in 2013 $ 2,328 Cash paid (267 ) Balance at December 31, 2013 $ 2,061 Expense recorded in 2014 6,025 Cash paid (856 ) Balance at December 31, 2014 $ 7,230 Expense recorded in 2015 5,367 Cash paid (426 ) Foreign currency translation 1 Balance at December 31, 2015 $ 12,172 Expense recorded in 2016 9,744 Cash paid (15,686 ) Foreign currency translation 2 Balance at December 31, 2016 $ 6,232 Expense recorded in 2017 3,204 Cash paid (7,173 ) Balance at December 31, 2017 $ 2,263 Cash paid (283 ) Balance at March 31, 2018 $ 1,980
Global Cost Reduction Program [Member]
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	The following table summarizes the activity to date related to this program: Expense recorded in 2015 $ 13,753 Cash paid (986 ) Foreign currency translation (150 ) Balance at December 31, 2015 $ 12,617 Expense recorded in 2016 9,918 Cash paid (16,237 ) Foreign currency translation (34 ) Balance at December 31, 2016 $ 6,264 Expense recorded in 2017 8,069 Cash paid (7,168 ) Foreign currency translation 500 Balance at December 31, 2017 $ 7,665 Cash paid (1,027 ) Foreign currency translation 148 Balance at March 31, 2018 $ 6,786
Restructuring expenses by segment [Table Text Block]	The following table summarizes the expense recognized by segment related to this program: Fiscal quarter ended April 1, 2017 Resistors & Inductors $ 851 Capacitors 161 Unallocated Selling, General, and Administrative Expenses 37 Total $ 1,049

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2018
Long-Term Debt [Abstract]
Schedule of long-term debt instruments	March 31, 2018 December 31, 2017 Credit facility $ 184,000 $ 150,000 Convertible senior debentures, due 2040 111,157 110,412 Convertible senior debentures, due 2041 57,031 56,641 Convertible senior debentures, due 2042 62,853 62,518 Deferred financing costs (8,656 ) (9,101 ) 406,385 370,470 Less current portion - - $ 406,385 $ 370,470
Key terms of the convertible debentures	The following table summarizes some key facts and terms regarding the three series of outstanding convertible senior debentures following the adjustment made to the conversion rate of the debentures on the ex-dividend date of the March 29, 2018 dividend payment: Due 2040 Due 2041 Due 2042 Issuance date November 9, 2010 May 13, 2011 May 31, 2012 Maturity date November 15, 2040 May 15, 2041 June 1, 2042 Principal amount $ 275,000 $ 150,000 $ 150,000 Cash coupon rate (per annum) 2.25 % 2.25 % 2.25 % Nonconvertible debt borrowing rate at issuance (per annum) 8.00 % 8.375 % 7.50 % Conversion rate effective March 14, 2018 (per $1 principal amount) 77.4680 56.5321 91.0838 Effective conversion price effective March 14, 2018 (per share) $ 12.91 $ 17.69 $ 10.98 130% of the conversion price (per share) $ 16.78 $ 23.00 $ 14.27 Call date November 20, 2020 May 20, 2021 June 7, 2022
Liability and equity of component of convertible senior debentures	The carrying values of the liability and equity components of the convertible debentures are reflected in the Company's consolidated condensed balance sheets as follows: Principal amount of the debentures Unamortized discount Embedded derivative Carrying value of liability component Equity component (including temporary equity) - net carrying value March 31, 2018 Due 2040 $ 275,000 (164,143 ) 300 $ 111,157 $ 110,094 Due 2041 $ 150,000 (93,239 ) 270 $ 57,031 $ 62,246 Due 2042 $ 150,000 (87,276 ) 129 $ 62,853 $ 57,874 Total $ 575,000 $ (344,658 ) $ 699 $ 231,041 $ 230,214 December 31, 2017 Due 2040 $ 275,000 (164,794 ) 206 $ 110,412 $ 110,094 Due 2041 $ 150,000 (93,573 ) 214 $ 56,641 $ 62,246 Due 2042 $ 150,000 (87,600 ) 118 $ 62,518 $ 57,874 Total $ 575,000 $ (345,967 ) $ 538 $ 229,571 $ 230,214
Convertible debentures, interest expense	Interest expense related to the debentures is reflected on the consolidated condensed statements of operations for the fiscal quarters ended: Contractual coupon interest Non-cash amortization of debt discount Non-cash amortization of deferred financing costs Non-cash change in value of derivative liability Total interest expense related to the debentures March 31, 2018 Due 2040 $ 1,547 651 22 94 $ 2,314 Due 2041 $ 844 334 12 56 $ 1,246 Due 2042 $ 844 324 13 11 $ 1,192 Total $ 3,235 $ 1,309 $ 47 $ 161 $ 4,752 April 1, 2017 Due 2040 $ 1,547 602 22 (25 ) $ 2,146 Due 2041 $ 844 308 12 2 $ 1,166 Due 2042 $ 844 301 13 (4 ) $ 1,154 Total $ 3,235 $ 1,211 $ 47 $ (27 ) $ 4,466

Accumulated Other Comprehensi30

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Abstract]
Summary of components of other comprehensive income	The cumulative balance of each component of other comprehensive income (loss) and the income tax effects allocated to each component are as follows: Pension and other post-retirement actuarial items Currency translation adjustment Unrealized gain (loss) on available-for-sale securities Total Balance at January 1, 2018 $ (69,041 ) $ 92,954 $ 1,801 $ 25,714 Cumulative effect of accounting for adoption of ASU 2016-01 - - (1,801 ) $ (1,801 ) Other comprehensive income before reclassifications - 27,024 - $ 27,024 Tax effect - - - $ - Other comprehensive income before reclassifications, net of tax - 27,024 - $ 27,024 Amounts reclassified out of AOCI 2,296 - - $ 2,296 Tax effect (689 ) - - $ (689 ) Amounts reclassified out of AOCI, net of tax 1,607 - - $ 1,607 Net other comprehensive income $ 1,607 $ 27,024 $ - $ 28,631 Balance at March 31, 2018 $ (67,434 ) $ 119,978 $ - $ 52,544

Pensions and Other Postretire31

Pensions and Other Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2018
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost for pension and other postretirement benefit plans	The following table shows the components of the net periodic pension cost for the first fiscal quarters of 2018 and 2017 for the Company's defined benefit pension plans: Fiscal quarter ended March 31, 2018 Fiscal quarter ended April 1, 2017 U.S. Plans Non-U.S. Plans U.S. Plans Non-U.S. Plans Net service cost $ - $ 948 $ - $ 903 Interest cost 371 1,242 410 1,167 Expected return on plan assets - (488 ) - (506 ) Amortization of prior service cost 36 55 36 18 Amortization of losses 159 1,604 82 1,478 Curtailment and settlement losses - 462 - 322 Net periodic benefit cost $ 566 $ 3,823 $ 528 $ 3,382
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost for pension and other postretirement benefit plans	The following table shows the components of the net periodic benefit cost for the first fiscal quarters of 2018 and 2017 for the Company's other postretirement benefit plans: Fiscal quarter ended March 31, 2018 Fiscal quarter ended April 1, 2017 U.S. Plans Non-U.S. Plans U.S. Plans Non-U.S. Plans Service cost $ 34 $ 75 $ 33 $ 64 Interest cost 68 30 77 24 Amortization of prior service (credit) (37 ) - (209 ) - Amortization of losses (gains) (10 ) 27 (23 ) 14 Net periodic benefit cost $ 55 $ 132 $ (122 ) $ 102

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Stock-Based Compensation [Abstract]
Summary of recognized stock-based compensation expense	The following table summarizes stock-based compensation expense recognized: Fiscal quarters ended March 31, 2018 April 1, 2017 Restricted stock units $ 2,269 $ 2,204 Phantom stock units 214 163 Total $ 2,483 $ 2,367
Schedule of unrecognized compensation cost, nonvested awards	The following table summarizes unrecognized compensation cost and the weighted average remaining amortization periods at March 31, 2018 (amortization periods in years) Unrecognized Compensation Cost Weighted Average Remaining Amortization Periods Restricted stock units $ 5,394 1.7 Phantom stock units - 0.0 Total $ 5,394
Schedule of share-based compensation, restricted stock units award activity	RSU activity under the 2007 Program as of March 31, 2018 and changes during the three fiscal months then ended are presented below (number of RSUs in thousands) Number of RSUs Weighted Average Grant-date Fair Value per Unit Outstanding: January 1, 2018 986 $ 13.34 Granted 252 18.90 Vested* (334 ) 13.67 Cancelled or forfeited - - Outstanding at March 31, 2018 904 $ 14.77 Expected to vest at March 31, 2018 904 * The number of RSUs vested includes shares that the Company withheld on behalf of employees to satisfy the statutory tax withholding requirements.
Schedule of share-based compensation arrangement by share-based units, vested and expected to vest	The number of performance-based RSUs that are scheduled to vest increases ratably based on the achievement of defined performance criteria between the established target and maximum levels. RSUs with performance-based vesting criteria are expected to vest as follows (number of RSUs in thousands) Vesting Date Expected to Vest Not Expected to Vest Total January 1, 2019 213 - 213 January 1, 2020 167 - 167 January 1, 2021 141 - 141
Schedule of share-based compensation, phantom stock units, Activity	Phantom stock unit activity under the phantom stock plan as of March 31, 2018 and changes during the three fiscal months then ended are presented below (number of phantom stock units in thousands) Number of units Grant-date Fair Value per Unit Outstanding: January 1, 2018 157 Granted 10 $ 21.35 Dividend equivalents issued 1 Outstanding at March 31, 2018 168

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Information [Abstract]
Schedule of Segment Reporting Information, by Segment	The following tables set forth business segment information: MOSFETs Diodes Optoelectronic Components Resistors & Inductors Capacitors Total Fiscal quarter ended March 31, 2018: Product Sales $ 127,494 $ 167,017 $ 71,958 $ 244,019 $ 106,268 $ 716,756 Royalty Revenues 12 - - 27 - $ 39 Total Revenue $ 127,506 $ 167,017 $ 71,958 $ 244,046 $ 106,268 $ 716,795 Gross Profit $ 32,022 $ 43,200 $ 27,233 $ 78,530 $ 24,315 $ 205,300 Segment Operating Income $ 22,558 $ 37,931 $ 22,794 $ 70,002 $ 18,893 $ 172,178 Fiscal quarter ended April 1, 2017:* Product Sales $ 104,842 $ 144,585 $ 65,262 $ 200,246 $ 89,860 $ 604,795 Royalty Revenues - - - 6 - $ 6 Total Revenue $ 104,842 $ 144,585 $ 65,262 $ 200,252 $ 89,860 $ 604,801 Gross Profit $ 20,717 $ 38,162 $ 22,442 $ 61,215 $ 19,213 $ 161,749 Segment Operating Income $ 11,803 $ 33,442 $ 17,117 $ 53,958 $ 14,190 $ 130,510 *Recast for the retrospective adoption of ASUs 2014-09 and 2017-07. See Note 1.
Reconciliation of Operating Profit (Loss) from Segments to Consolidated	Fiscal quarters ended March 31, 2018 April 1, 2017*** Reconciliation: Segment Operating Income $ 172,178 $ 130,510 Restructuring and Severance Costs - (1,469 ) Unallocated Selling, General, and Administrative Expenses (68,116 ) (61,463 ) Consolidated Operating Income 104,062 $ 67,578 Unallocated Other Income (Expense) (12,043 ) (17,136 ) Consolidated Income Before Taxes $ 92,019 50,442 ***Recast for the adoption of ASU 2017-07. See Note 1.
Disaggregation of Revenue [Table Text Block]	The Company has a broad line of products that it sells to OEMs, EMS companies, and independent distributors. The distribution of sales by customer type is shown below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Distributors $ 404,060 $ 345,703 $ 1,484,276 $ 1,280,060 OEMs 264,050 214,647 931,291 861,322 EMS companies 48,685 44,451 183,801 175,946 Total Revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328 Net revenues were attributable to customers in the following regions: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Asia $ 285,478 $ 257,058 $ 1,091,107 $ 948,195 Europe 267,382 206,025 902,357 810,543 Americas 163,935 141,718 605,904 558,590 Total Revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328 The Company generates substantially all of its revenue from product sales to end customers in the industrial, automotive, telecommunications, computing, consumer products, power supplies, military and aerospace, and medical end markets. Sales by end market are presented below: Fiscal quarters ended Years Ended December 31, March 31, 2018 April 1, 2017 2017 2016 Industrial $ 280,212 $ 216,766 $ 934,631 $ 796,031 Automotive 208,394 175,343 727,220 640,767 Telecommunications 45,924 45,835 190,682 193,456 Computing 47,431 41,070 198,850 172,481 Consumer Products 37,259 29,607 145,243 150,741 Power Supplies 34,243 34,858 160,038 132,555 Military and Aerospace 35,214 33,176 132,898 128,523 Medical 28,118 28,146 109,806 102,774 Total revenue $ 716,795 $ 604,801 $ 2,599,368 $ 2,317,328

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted earnings per share attributable to Vishay stockholders (shares in thousands) Fiscal quarters ended March 31, 2018 April 1, 2017 Numerator: Net earnings attributable to Vishay stockholders $ 62,366 $ 36,719 Denominator: Denominator for basic earnings per share: Weighted average shares 144,160 146,120 Outstanding phantom stock units 167 154 Adjusted weighted average shares - basic 144,327 146,274 Effect of dilutive securities: Convertible and exchangeable debt instruments 14,610 8,349 Restricted stock units 565 253 Dilutive potential common shares 15,175 8,602 Denominator for diluted earnings per share: Adjusted weighted average shares - diluted 159,502 154,876 Basic earnings per share attributable to Vishay stockholders $ 0.43 $ 0.25 Diluted earnings per share attributable to Vishay stockholders $ 0.39 $ 0.24
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Diluted earnings per share for the periods presented do not reflect the following weighted average potential common shares that would have an antidilutive effect or have unsatisfied performance conditions (in thousands) Fiscal quarters ended March 31, 2018 April 1, 2017 Convertible and exchangeable notes: Convertible Senior Debentures, due 2041 - 8,340 Weighted average other 307 581

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Measurements [Abstract]
Schedule of fair Value, Assets and Liabilities Measured on Recurring basis	The following table provides the financial assets and liabilities carried at fair value measured on a recurring basis: Total Fair Value Level 1 Level 2 Level 3 March 31, 2018 Assets: Assets held in rabbi trusts $ 43,756 $ 27,199 $ 16,557 $ - Available for sale securities $ 4,702 4,702 - - $ 48,458 $ 31,901 $ 16,557 $ - Liabilities: Embedded derivative - convertible debentures due 2040 $ (300 ) $ - $ - $ (300 ) Embedded derivative - convertible debentures due 2041 $ (270 ) - - (270 ) Embedded derivative - convertible debentures due 2042 $ (129 ) - - (129 ) $ (699 ) $ - $ - $ (699 ) December 31, 2017 Assets: Assets held in rabbi trusts $ 45,252 $ 28,589 16,663 $ - Available for sale securities $ 4,621 4,621 - - $ 49,873 $ 33,210 $ 16,663 $ - Liabilities: Embedded derivative - convertible debentures due 2040 $ (206 ) $ - $ - $ (206 ) Embedded derivative - convertible debentures due 2041 $ (214 ) - - (214 ) Embedded derivative - convertible debentures due 2042 $ (118 ) - - (118 ) $ (538 ) $ - $ - $ (538 )

Basis of Presentation (Details)

Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net revenues	$ 716,795	$ 673,462	$ 677,941	$ 643,164	$ 604,801	$ 2,599,368	$ 2,317,328
Costs of products sold	511,495	496,086	487,794	469,327	443,052	1,896,259	1,743,506
Gross profit	205,300	177,376	190,147	173,837	161,749	703,109	573,822
Operating Income	104,062	76,006	95,416	85,005	67,578	324,005	197,058
Total other income (expense)	(12,043)	(8,981)	(9,228)	(9,296)	(17,136)	(44,641)	(102,842)
Income before taxes	92,019	67,025	86,188	75,709	50,442	279,364	94,216
Income tax expense	29,474	244,526	21,605	19,300	13,493	298,924	44,843
Net earnings (loss)	62,545	(177,501)	64,583	56,409	36,949	(19,560)	49,373
Less: net earnings attributable to noncontrolling interests	179	156	179	219	230	784	581
Net earnings (loss) attributable to Vishay stockholders	$ 62,366	(177,657)	64,404	56,190	36,719	(20,344)	48,792
Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net revenues		674,489	677,883	644,892	606,258	2,603,522	2,323,431
Costs of products sold		497,988	488,610	471,929	445,383	1,903,910	1,753,648
Gross profit		176,501	189,273	172,963	160,875	699,612	569,783
Operating Income		72,536	92,328	82,036	64,688	311,588	101,717
Total other income (expense)		(5,511)	(6,140)	(6,327)	(14,246)	(32,224)	(7,501)
Income before taxes		67,025	86,188	75,709	50,442	279,364	94,216
Income tax expense		244,526	21,605	19,300	13,493	298,924	44,843
Net earnings (loss)		(177,501)	64,583	56,409	36,949	(19,560)	49,373
Less: net earnings attributable to noncontrolling interests		156	179	219	230	784	581
Net earnings (loss) attributable to Vishay stockholders		(177,657)	64,404	56,190	36,719	(20,344)	48,792
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net revenues		(1,027)	58	(1,728)	(1,457)	(4,154)	(6,103)
Costs of products sold		(1,902)	(816)	(2,602)	(2,331)	(7,651)	(10,142)
Gross profit		875	874	874	874	3,497	4,039
Operating Income		3,470	3,088	2,969	2,890	12,417	95,341
Total other income (expense)		(3,470)	(3,088)	(2,969)	(2,890)	(12,417)	(95,341)
Income before taxes		0	0	0	0	0	0
Income tax expense		0	0	0	0	0	0
Net earnings (loss)		0	0	0	0	0	0
Less: net earnings attributable to noncontrolling interests		0	0	0	0	0	0
Net earnings (loss) attributable to Vishay stockholders		$ 0	$ 0	$ 0	$ 0	$ 0	0
U.S. pension settlement charges							$ (79,321)

Revenue Recognition Policies (D

Revenue Recognition Policies (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2016
Distributor sales accruals [Line Items]
Distributor sales accrual, Beginning Balance	$ 36,680	$ 34,479	$ 34,479	$ 32,487
Distributor sales accrual, sales allowance	24,188	21,520	89,009	86,896
Distributor sales accrual, credits issued	(28,450)	(23,471)	(87,403)	(85,341)
Distributor sales accrual, foreign currency	288	(576)	595	437
Distributor sales accrual, Ending Balance	$ 32,706	$ 31,952	$ 36,680	$ 34,479

Acquisition Activities (Details

Acquisition Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Acquisition of business, net of cash acquired	$ 12,072	$ 0
UltraSource [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Purchase price of businesses	13,372
Finite-lived Intangible Assets Acquired	6,500
Goodwill related to acquisitions	$ 4,003
Business Acquisition, Name of Acquired Entity	UltraSource, Inc.
Business Acquisition, Effective Date of Acquisition	Feb. 8, 2018

Restructuring and Related Act39

Restructuring and Related Activities (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Reserve [Roll Forward]
Restructuring and severance costs	$ 0	$ 1,469
MOSFETs Enhanced Competitiveness Program [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Current	1,980
Restructuring Reserve [Roll Forward]
Restructuring and severance costs		420	$ 3,204	$ 9,744	$ 5,367	$ 6,025	$ 2,328
Cash paid	(283)		(7,173)	(15,686)	(426)	(856)	(267)
Foreign currency translation				2	1
Balance at end of period	1,980		2,263	6,232	12,172	7,230	$ 2,061
Balance at beginning of period	$ 2,263	6,232	6,232	12,172	7,230	$ 2,061
Term of restructuring program	2 years
Global Cost Reduction Program [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Current	$ 4,222
Restructuring Reserve [Roll Forward]
Restructuring and severance costs		1,049	8,069	9,918	13,753
Cash paid	(1,027)		(7,168)	(16,237)	(986)
Foreign currency translation	148		500	(34)	(150)
Balance at end of period	6,786		7,665	6,264	$ 12,617
Balance at beginning of period	$ 7,665	6,264	$ 6,264	$ 12,617
Global Cost Reduction Program [Member] | Resistors And Inductors Segment [Member]
Restructuring Reserve [Roll Forward]
Restructuring and severance costs		851
Global Cost Reduction Program [Member] | Capacitors Segment [Member]
Restructuring Reserve [Roll Forward]
Restructuring and severance costs		161
Global Cost Reduction Program [Member] | Unallocated Amount to Segment [Member]
Restructuring Reserve [Roll Forward]
Restructuring and severance costs		$ 37

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017
Income Taxes [Abstract]
Increase in liabilities for unrecognized tax benefits	$ 568
TCJA income tax expense Abstract [Abstract]
TCJA tax on unremitted foreign earnings			$ 215,558
TCJA foreign taxes on assumed repatriation			213,000
Expected TCJA tax payment, net	180,000
Additional expected repatriation			$ 1,100,000
Cash repatriated during the current period	0
Remeasurement of repatriation deferred tax liability [Member]
Effect on Income Tax Expense (Benefit) [Line Items]
Deferred Other Tax Expense (Benefit)	$ 1,316	$ (968)

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Credit facility	$ 184,000		$ 150,000
Deferred Financing Costs	(8,656)		(9,101)
Long-term debt	406,385		370,470
Less current portion	0		0
Long-term debt, less current portion	$ 406,385		370,470
Debt Instruments [Abstract]
Debt instrument percentage of conversion price (in hundredths)	130.00%
Debt instrument, Percentage of sale price of common stock (in hundredths)	98.00%
Liability and equity components of convertible debentures [Abstract]
Principal amount of the debentures	$ 575,000		575,000
Unamortized discount	(344,658)		(345,967)
Embedded derivative	699		538
Carrying value of liability component	231,041		229,571
Equity component - net carrying value	230,214		230,214
Interest expense related to debentures [Abstract]
Contractual coupon interest	3,235	$ 3,235
Non-cash amortization of debt discount	1,309	1,211
Non-cash amortization of deferred financing costs	47	47
Non-cash change in value of derivative liability	161	(27)
Total interest expense related to the debentures	4,752	4,466
Convertible Senior Debentures, Due 2040 [Member]
Debt Instrument [Line Items]
Convertible Debt, Noncurrent	$ 111,157		110,412
Debt Instruments [Abstract]
Issuance date	Nov. 9, 2010
Debt maturity date	Nov. 15, 2040
Stated rate of interest on debt (in hundredths)	2.25%
Effective rate of interest on convertible senior debentures (in hundredths)	8.00%
Debt conversion rate	77.4680
Debt effective conversion price	$ 12.91
Debt Instrument, Convertible, Stock Price Trigger	$ 16.78
Convertible senior debentures call date	Nov. 20, 2020
Liability and equity components of convertible debentures [Abstract]
Principal amount of the debentures	$ 275,000		275,000
Unamortized discount	(164,143)		(164,794)
Embedded derivative	300		206
Carrying value of liability component	111,157		110,412
Equity component - net carrying value	110,094		110,094
Interest expense related to debentures [Abstract]
Contractual coupon interest	1,547	1,547
Non-cash amortization of debt discount	651	602
Non-cash amortization of deferred financing costs	22	22
Non-cash change in value of derivative liability	94	(25)
Total interest expense related to the debentures	2,314	2,146
Convertible Senior Debentures, Due 2041 [Member]
Debt Instrument [Line Items]
Convertible Debt, Noncurrent	$ 57,031		56,641
Debt Instruments [Abstract]
Issuance date	May 13, 2011
Debt maturity date	May 15, 2041
Stated rate of interest on debt (in hundredths)	2.25%
Effective rate of interest on convertible senior debentures (in hundredths)	8.375%
Debt conversion rate	56.5321
Debt effective conversion price	$ 17.69
Debt Instrument, Convertible, Stock Price Trigger	$ 23
Convertible senior debentures call date	May 20, 2021
Liability and equity components of convertible debentures [Abstract]
Principal amount of the debentures	$ 150,000		150,000
Unamortized discount	(93,239)		(93,573)
Embedded derivative	270		214
Carrying value of liability component	57,031		56,641
Equity component - net carrying value	62,246		62,246
Interest expense related to debentures [Abstract]
Contractual coupon interest	844	844
Non-cash amortization of debt discount	334	308
Non-cash amortization of deferred financing costs	12	12
Non-cash change in value of derivative liability	56	2
Total interest expense related to the debentures	1,246	1,166
Convertible Senior Debentures, Due 2042 [Member]
Debt Instrument [Line Items]
Convertible Debt, Noncurrent	$ 62,853		62,518
Debt Instruments [Abstract]
Issuance date	May 31, 2012
Debt maturity date	Jun. 1, 2042
Stated rate of interest on debt (in hundredths)	2.25%
Effective rate of interest on convertible senior debentures (in hundredths)	7.50%
Debt conversion rate	91.0838
Debt effective conversion price	$ 10.98
Debt Instrument, Convertible, Stock Price Trigger	$ 14.27
Convertible senior debentures call date	Jun. 7, 2022
Liability and equity components of convertible debentures [Abstract]
Principal amount of the debentures	$ 150,000		150,000
Unamortized discount	(87,276)		(87,600)
Embedded derivative	129		118
Carrying value of liability component	62,853		62,518
Equity component - net carrying value	57,874		$ 57,874
Interest expense related to debentures [Abstract]
Contractual coupon interest	844	844
Non-cash amortization of debt discount	324	301
Non-cash amortization of deferred financing costs	13	13
Non-cash change in value of derivative liability	11	(4)
Total interest expense related to the debentures	$ 1,192	$ 1,154

Accumulated Other Comprehensi42

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	$ 25,714
Cumulative effect of accounting change for adoption of ASU			$ 0	$ 386	$ 2,210
Other comprehensive income (loss)	28,631	$ 19,899	120,366	36,675
Ending Balance	52,544		25,714
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	1,801
Cumulative effect of accounting change for adoption of ASU			(1,801)
Other comprehensive income before reclassifications	0
Tax effect	0
Other comprehensive income before reclassifications, net of tax	0
Amounts reclassified out of AOCI	0
Tax effect of reclassification	0
Amounts reclassified out of AOCI, net of tax	0
Other comprehensive income (loss)	0
Ending Balance	0		1,801
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	92,954
Cumulative effect of accounting change for adoption of ASU			0
Other comprehensive income before reclassifications	27,024
Tax effect	0
Other comprehensive income before reclassifications, net of tax	27,024
Amounts reclassified out of AOCI	0
Tax effect of reclassification	0
Amounts reclassified out of AOCI, net of tax	0
Other comprehensive income (loss)	27,024
Ending Balance	119,978		92,954
Pension and Other Post-Retirement Actuarial Items [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(69,041)
Cumulative effect of accounting change for adoption of ASU			0
Other comprehensive income before reclassifications	0
Tax effect	0
Other comprehensive income before reclassifications, net of tax	0
Amounts reclassified out of AOCI	2,296
Tax effect of reclassification	(689)
Amounts reclassified out of AOCI, net of tax	1,607
Other comprehensive income (loss)	1,607
Ending Balance	(67,434)		(69,041)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	25,714
Cumulative effect of accounting change for adoption of ASU			(1,801)	0	$ 0
Other comprehensive income before reclassifications	27,024
Tax effect	0
Other comprehensive income before reclassifications, net of tax	27,024
Amounts reclassified out of AOCI	2,296
Tax effect of reclassification	(689)
Amounts reclassified out of AOCI, net of tax	1,607
Other comprehensive income (loss)	28,631		120,366	$ 36,675
Ending Balance	$ 52,544		$ 25,714

Pensions and Other Postretire43

Pensions and Other Postretirement Benefits (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Defined Benefit Pension Plan [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	$ 0	$ 0
Interest cost	371	410
Expected return on plan assets	0	0
Amortization of prior service cost (credit)	36	36
Amortization of losses (gains)	159	82
Curtailments and settlements	0	0
Net periodic benefit cost	566	528
Defined Benefit Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	948	903
Interest cost	1,242	1,167
Expected return on plan assets	(488)	(506)
Amortization of prior service cost (credit)	55	18
Amortization of losses (gains)	1,604	1,478
Curtailments and settlements	462	322
Net periodic benefit cost	3,823	3,382
Other Postretirement Benefits [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	34	33
Interest cost	68	77
Amortization of prior service cost (credit)	(37)	(209)
Amortization of losses (gains)	(10)	(23)
Net periodic benefit cost	55	(122)
Other Postretirement Benefits [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	75	64
Interest cost	30	24
Amortization of prior service cost (credit)	0	0
Amortization of losses (gains)	27	14
Net periodic benefit cost	$ 132	$ 102

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
		Mar. 31, 2018	Apr. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		$ 2,483	$ 2,367
Unrecognized Compensation Cost		$ 5,394
Expiration date of the 2007 stock incentive plan		May 20, 2024
Maximum number of shares granted under restricted stock, unrestricted stock, RSU's and stock options to officers, employees and employee directors (in shares)		6,500,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		$ 2,269	2,204
Unrecognized Compensation Cost		$ 5,394
Weighted Average Remaining Amortization Periods		1 year 8 months 12 days
Equity Awards Other Than Options Outstanding:
Balance (in shares)		986,000
Balance (in dollars per share)		$ 13.34
Granted (in shares)		252,000
Granted (in dollars per share)		$ 18.90
Vested (in shares)	[1]	(334,000)
Vested (in dollars per share)	[1]	$ 13.67
Cancelled or forfeited (in shares)		0
Cancelled or forfeited (in dollars per share)		$ 0
Balance (in shares)		904,000
Balance (in dollars per share)		$ 14.77
Expected to vest (in shares)		904,000
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recognized		$ 214	$ 163
Unrecognized Compensation Cost		$ 0
Weighted Average Remaining Amortization Periods		0 years
Equity Awards Other Than Options Outstanding:
Balance (in shares)		157,000
Granted (in shares)		10,000
Granted (in dollars per share)		$ 21.35
Dividend equivalents issued		1,000
Balance (in shares)		168,000
Scheduled to Vest January 1, 2019 [Member] | Performance Vested Restricted Stock Units [Member]
Equity Awards Other Than Options Outstanding:
Balance (in shares)		213,000
Expected to vest (in shares)		213,000
Not expected to vest (in shares)		0
Scheduled to Vest January 1, 2020 [Member] | Performance Vested Restricted Stock Units [Member]
Equity Awards Other Than Options Outstanding:
Balance (in shares)		167,000
Expected to vest (in shares)		167,000
Not expected to vest (in shares)		0
Scheduled to Vest January 1, 2021 [Member] | Performance Vested Restricted Stock Units [Member]
Equity Awards Other Than Options Outstanding:
Balance (in shares)		141,000
Expected to vest (in shares)		141,000
Not expected to vest (in shares)		0
[1]	The number of RSUs vested includes shares that the Company withheld on behalf of employees to satisfy the statutory tax withholding requirements.

Segment Information (Details)

Segment Information (Details) $ in Thousands	3 Months Ended					12 Months Ended
	Mar. 31, 2018USD ($)Segment	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jul. 01, 2017USD ($)	Apr. 01, 2017USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment	5
Product Sales	$ 716,756				$ 604,795
Royalty Revenues	39				6
Total Revenue	716,795	$ 673,462	$ 677,941	$ 643,164	604,801	$ 2,599,368	$ 2,317,328
Gross Margin	205,300	177,376	190,147	173,837	161,749	703,109	573,822
Segment Operating Income	172,178				130,510
Restructuring and severance Costs	0				(1,469)
Operating income	104,062	76,006	95,416	85,005	67,578	324,005	197,058
Unallocated Other Income (Expense)	(12,043)	(8,981)	(9,228)	(9,296)	(17,136)	(44,641)	(102,842)
Income before taxes	92,019	$ 67,025	$ 86,188	$ 75,709	50,442	279,364	94,216
Distributors [Member]
Segment Reporting Information [Line Items]
Total Revenue	404,060				345,703	1,484,276	1,280,060
OEMs [Member]
Segment Reporting Information [Line Items]
Total Revenue	264,050				214,647	931,291	861,322
EMS companies [Member]
Segment Reporting Information [Line Items]
Total Revenue	48,685				44,451	183,801	175,946
Industrial [Member]
Segment Reporting Information [Line Items]
Total Revenue	280,212				216,766	934,631	796,031
Automotive [Member]
Segment Reporting Information [Line Items]
Total Revenue	208,394				175,343	727,220	640,767
Telecommunications [Member]
Segment Reporting Information [Line Items]
Total Revenue	45,924				45,835	190,682	193,456
Computing [Member]
Segment Reporting Information [Line Items]
Total Revenue	47,431				41,070	198,850	172,481
Consumer Products [Member]
Segment Reporting Information [Line Items]
Total Revenue	37,259				29,607	145,243	150,741
Power Supplies [Member]
Segment Reporting Information [Line Items]
Total Revenue	34,243				34,858	160,038	132,555
Military and Aerospace [Member]
Segment Reporting Information [Line Items]
Total Revenue	35,214				33,176	132,898	128,523
Medical [Member]
Segment Reporting Information [Line Items]
Total Revenue	28,118				28,146	109,806	102,774
Asia [Member]
Segment Reporting Information [Line Items]
Total Revenue	285,478				257,058	1,091,107	948,195
Americas [Member]
Segment Reporting Information [Line Items]
Total Revenue	163,935				141,718	605,904	558,590
Europe [Member]
Segment Reporting Information [Line Items]
Total Revenue	267,382				206,025	$ 902,357	$ 810,543
MOSFETS Segment [Member]
Segment Reporting Information [Line Items]
Product Sales	127,494				104,842
Royalty Revenues	12				0
Total Revenue	127,506				104,842
Gross Margin	32,022				20,717
Segment Operating Income	22,558				11,803
Diodes Segment [Member]
Segment Reporting Information [Line Items]
Product Sales	167,017				144,585
Royalty Revenues	0				0
Total Revenue	167,017				144,585
Gross Margin	43,200				38,162
Segment Operating Income	37,931				33,442
Optoelectronic Components Segment [Member]
Segment Reporting Information [Line Items]
Product Sales	71,958				65,262
Royalty Revenues	0				0
Total Revenue	71,958				65,262
Gross Margin	27,233				22,442
Segment Operating Income	22,794				17,117
Resistors And Inductors Segment [Member]
Segment Reporting Information [Line Items]
Product Sales	244,019				200,246
Royalty Revenues	27				6
Total Revenue	244,046				200,252
Gross Margin	78,530				61,215
Segment Operating Income	70,002				53,958
Capacitors Segment [Member]
Segment Reporting Information [Line Items]
Product Sales	106,268				89,860
Royalty Revenues	0				0
Total Revenue	106,268				89,860
Gross Margin	24,315				19,213
Segment Operating Income	18,893				14,190
Unallocated Amount to Segment [Member]
Segment Reporting Information [Line Items]
Segment Operating Income	(68,116)				(61,463)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment Operating Income	172,178				130,510
Unallocated Amount to Segment [Member]
Segment Reporting Information [Line Items]
Restructuring and severance Costs	0				(1,469)
Unallocated Other Income (Expense)	$ (12,043)				$ (17,136)

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended					12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2017	Dec. 31, 2016
Numerator for basic earnings per share:
Net earnings attributable to Vishay stockholders	$ 62,366	$ (177,657)	$ 64,404	$ 56,190	$ 36,719	$ (20,344)	$ 48,792
Denominator for basic earnings per share:
Weighted average shares	144,160				146,120
Outstanding phantom stock units	167				154
Adjusted weighted average shares (basic)	144,327				146,274
Effect of dilutive securities:
Convertible and exchangeable debt instruments	14,610				8,349
Restricted stock units	565				253
Dilutive potential common shares	15,175				8,602
Denominator for diluted earnings per share:
Adjusted weighted average shares (diluted)	159,502				154,876
Basic earnings per share attributable to Vishay stockholders (in dollars per share)	$ 0.43				$ 0.25
Diluted earnings per share attributable to Vishay stockholders (in dollars per share)	0.39				$ 0.24
Convertible Senior Debentures, Due 2040 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Minimum market price of common stock for inclusion of shares issuable upon conversion of senior debentures for calculation of diluted earnings per share (in dollars per share)	$ 12.91
Convertible Senior Debentures, Due 2041 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount (in shares)	0				8,340
Minimum market price of common stock for inclusion of shares issuable upon conversion of senior debentures for calculation of diluted earnings per share (in dollars per share)	$ 17.69
Convertible Senior Debentures, Due 2042 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Minimum market price of common stock for inclusion of shares issuable upon conversion of senior debentures for calculation of diluted earnings per share (in dollars per share)	$ 10.98
Weighted average other [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount (in shares)	307				581

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Assets:
Held-to-maturity Securities, Transferred Security, at Carrying Value	$ 0
Held-to-maturity Securities, Unrecognized Holding Gain	0
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities	0
Liabilities:
Embedded derivative	(699)	$ (538)
Long-term Debt, Fair Value	1,015,400	1,071,200
Carrying value of long-term debt, excluding derivative liabilities	414,342	379,033
Derivative, Notional Amount	100,000	100,000
Fair Value, Measurements, Recurring [Member]
Assets:
Assets held in rabbi trusts	43,756	45,252
Available for sale securities	4,702	4,621
Fair Value Assets	48,458	49,873
Liabilities:
Fair Value Liabilities	(699)	(538)
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Assets held in rabbi trusts	27,199	28,589
Available for sale securities	4,702	4,621
Fair Value Assets	31,901	33,210
Liabilities:
Fair Value Liabilities	0	0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Assets held in rabbi trusts	16,557	16,663
Available for sale securities	0	0
Fair Value Assets	16,557	16,663
Liabilities:
Fair Value Liabilities	0	0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Assets held in rabbi trusts	0	0
Available for sale securities	0	0
Fair Value Assets	0	0
Liabilities:
Fair Value Liabilities	(699)	(538)
Convertible Senior Debentures, Due 2040 [Member]
Liabilities:
Embedded derivative	(300)	(206)
Convertible Senior Debentures, Due 2040 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	(300)	(206)
Convertible Senior Debentures, Due 2040 [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2040 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2040 [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	(300)	(206)
Convertible Senior Debentures, Due 2041 [Member]
Liabilities:
Embedded derivative	(270)	(214)
Convertible Senior Debentures, Due 2041 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	(270)	(214)
Convertible Senior Debentures, Due 2041 [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2041 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2041 [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	(270)	(214)
Convertible Senior Debentures, Due 2042 [Member]
Liabilities:
Embedded derivative	(129)	(118)
Convertible Senior Debentures, Due 2042 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	(129)	(118)
Convertible Senior Debentures, Due 2042 [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2042 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	0	0
Convertible Senior Debentures, Due 2042 [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities:
Embedded derivative	$ (129)	$ (118)